Throughout his career, Lichtenstein drew in various types of sketchbooks, spiral notebooks and drawing pads. In this catalogue raisonné, books or pads containing drawings are called sketchbooks; three also include printed paper clippings.

Each sketchbook entry is an umbrella record describing the book as a whole. Individual page entries are hyperlinked for easy navigation. Loose drawings are hyperlinked as "formerly in sketchbook" or "likely originating in sketchbook" when believed by the authors to have originated in them.

A Note on Page Numbering: 

Leaves are the sheets in a sketchbook. All extant leaves in Lichtenstein's sketchbooks were assigned consecutive page numbers, one number per leaf. When a leaf was drawn on on both sides, or only on the verso, "r" (recto) and "v" (verso) were added to the page number.

Entries for pages with drawings by the artist were assigned consecutive catalogue numbers irrespective of page numbers. 

See also 4.12. NOTEBOOKS

Resources 

For media definitions, the Philadelphia Museum of Art’s Descriptive Terminology for Works of Art on Paper was primarily consulted; for binding definitions, Ligatus's Language of Bindings. Descriptions of color and texture of paper are assigned by comparison to paper samples published in The Print Council of America Paper Sample Book. Descriptions of other materials, such as covers of spiral ring bindings, book covering materials, and any other aspects that do not adhere to these standards are in accord with the authors’ interpretations.

Main resources have been: 

Ash, Nancy, Scott Homolka, and Stephanie Lussier. Descriptive Terminology for Works of Art on Paper. Philadelphia: Philadelphia Museum of Art, 2014.     http://www.philamuseum.org/conservation/22.html

Language of Bindings. Ligatus. Accessed January 14, 2016. http://www.ligatus.org.uk/lob/help

Lunning, Elizabeth, and Roy Perkinson. The Print Council of America Paper Sample Book: A Practical Guide to the Description of Paper. The Print Council of America, 1996.

Roberts, Matt T., and Don Etherington. Bookbinding and the Conservation of Books: A Dictionary of Descriptive Terminology. Accessed June 5, 2015.
http://cool.conservation-us.org/don//toc/toc1.html

Umbrella Records

Sketchbook Titles

Originally, the artist’s sketchbooks were assigned letters by Foundation staff. For this catalogue, we assigned titles based on either the manufacturer or the commissioner/distributor, and other confirmed information (for more on sketchbook manufacture, see Appendix below).

For multiple sketchbooks from the same source, qualifying information was added to the titles:
- when distinguished by appearance the titles incorporate identifying features such as cover colors or cover patterns 
- when differing only in size, the terms small, medium and large were added or, when comparing two books, one book's title has no size distinction and the other is labeled as large.

Sketchbooks that are identical (except for their history of use) were titled according to the guidelines above, adding a number in square brackets assigned chronologically following the date of what we assume is the earliest work in that sketchbook or, in two cases, the date of the loose drawings we believe originated in them.

For the Strathmore sketchbooks, the manufacturer name is followed by the sketchbook/paper name printed on the front covers.

In the case of a Composition notebook with an unidentified manufacturer, the title derives from the name printed on the front cover.

Sketchbooks for which no source information could be found were named according to their appearance (e.g., Black Sketchbook, Floral Print Sketchbook). 

A sketchbook that belonged to Lichtenstein’s first wife, Isabel, is included because it contains some of the artist’s drawings. Its title, Isabel Wilson’s Sketchbook, reflects the name on their marriage certificate.

Sketchbook Images

Each sketchbook umbrella record shows both front and back covers of the book as Primary Images.

Research Images are added to document any of the following:

- watermarks, in black-and-white for emphasis 
- laid paper structure, in black-and-white for emphasis 
- loose material found inside the book
- stubs with traces of a removed drawing 
- pages with marks, but no drawing (since pages of marks may be of interest, but do not merit artwork records) 
- pages with cutouts when they have been matched with loose drawings 
- pages with linear depressions from the pressure of drawing on another sheet when the linear depressions have been matched with a loose drawing or are otherwise noteworthy (e.g. RLCR 1998, depressions from drawing of chemical molecules)
- pages with drawings by others 

Sketchbook Dates/Signatures

The artist did not sign or date his sketchbooks. Date(s) assigned to the umbrella records are based on the year(s) of the drawings in a sketchbook, in other words, the year(s) we believe the artist first conceived an idea, either following the confirmed dates of related finished artworks, or considering the time span over which we assume the artist was working on a group of works.

Media/Support

Indicated here are mediums employed by the artist throughout a sketchbook. Graphite pencil and colored pencil are the primary mediums found. Where applicable, more detailed information is provided in the individual drawing (page) records. Support is the paper comprising the text block, which we define as all the leaves in the sketchbook, except for the endpapers. Further paper characterization (color, thickness, etc.) is provided in the Description. If parts of pages have been removed by cutting or tearing, "cutout" (e.g., RLCR 3602) or "tear-out" (e.g., RLCR 1502) is listed after the support. Any loose material found inside a sketchbook is listed last.

Sketchbook Dimensions

Height, width, and depth (or thickness) of the binding are followed by the approximate length and width of the leaves, to the sixteenth of an inch. When endcaps and/or endbands obscure the spine edge (edge removed from the book) of the text block, leaf dimensions were approximated.

Leaf dimensions listed in an umbrella record are not repeated in the records of the individual sketchbook pages; image dimensions are only listed in the individual page records (and only when the artist drew a border line around a sketch).   

Sketchbook Format/Drawing Orientation

For case bindings, the sketchbook format reflects the book’s longest axis when the spine is vertical. For spiral bindings and perfect bindings, the format of the sketchbook is determined by the book’s longest axis when existing manufacturer or distributor marks are right-reading. Otherwise, format is up to the discretion of the authors (for example RLCR 253 in which the sketchbook orientation is determined by the watercolor on the book’s front page).

Drawing orientation, which varies in most sketchbooks, is defined in relation to the sketchbook format.

Sketchbook Extent

Extent is the total number of leaves original to the sketchbook. The number is sometimes printed on the front cover, but usually had to be determined from the sum of used, blank, and missing leaves. If flyleaves exist, they are included in this count. Due to the difficulty of collating adhesive- and spiral-bound books with missing pages (and no extent indicated by the manufacturer), the authors sometimes estimated the extent.

Used leaves
Listed here is the number of leaves used or manipulated but not removed by the artist (or, in rare cases, his wife, Dorothy Lichtenstein; an assistant, Patricia Koch; and his son, Mitchell). These include leaves with drawings, notes and marks, and cutouts as well as attached material. Catalogue record numbers were assigned only to leaves with drawings by the artist; pages with notes or drawings by others, however, are illustrated as Research Images. Thus the number of used leaves may not always match the total number of records for a sketchbook.

Blank leaves
The number of unused leaves remaining in a sketchbook.

Missing leaves
The number of leaves removed from the sketchbook. This count is based on the number of stubs (small fragments from leaves remaining in the sketchbook) along with the collation of the sewn book. For adhesive-, and spiral-bound books, we relied on manufacturer’s information on the covers; if there was no manufacturer information, we counted any stubs, but did not attempt to estimate the total number of removed pages.

Binding Description

The sketchbooks have either a case binding, sewn binding, spiral binding or adhesive binding. The binding type, or method of attaching the text block to the covers, is provided. The hardcover sketchbook bindings are case bindings. Other binding types are adhesive bindings, bound with adhesive directly to the covering material, and spiral bindings, in which perforated leaves are attached to a spiral ring. 

For case bindings, the sketchbook style, or application of covering material, is included (e.g. parchment along spine). Full style uses one material to cover the book. Half style typically involves two materials (e.g. paper and leather): one covers the boards and another covers the spine and corners. Quarter style also typically involves two materials: one covers the boards and another covers the spine. The covering material, including cloth, paper or parchment, and its appearance is characterized. 

The method used to construct the text block of case bindings is identified here as thread sewing or adhesive-bound. Construction is implied for spiral and adhesive binding types.

The only sketchbooks that possess endbands are case bindings, for which we either describe the endband, or write "no endbands," respectively.

Paper Description

Text block paper manufacture is characterized as handmade, machine-made and mould-made. If the method is unclear, a question mark indicates uncertainty. The structure of the paper—laid or wove—is identified and the texture and color are given, as defined by paper samples published by Lunning and Perkinson 1996. The edge finish of text block leaves is recorded. Most edges have been cut.

If a watermark is present, text is transcribed and symbols are characterized within square brackets (e.g., [lion]). If watermarks are consistently in the same place throughout, the location is indicated. Otherwise, it is noted that the location varies. The frequency of occurrence of watermarks is also described (e.g., on every page, or on some pages). If there are no watermarks, this is stated.

Paper thickness is given, as measured with a Lithco Pocket Gauge, in inches.

For sketchbooks with case binding and endpaper (pastedowns and flyleaves at the beginning and end of a book, at times used by the artist for drawing), we either described the endpaper with the same terminology as the leaves of the book, or we wrote "no endpaper," respectively. For spiral bindings, adhesive bindings and Composition notebooks, the absence of endpaper is implied.

Condition
Condition issues related to the artist’s use of the sketchbook are described here (e.g., the presence of incisions, stray media, and eraser crumbs). 

Manufacturer
The primary contributor(s) to a sketchbook's manufacture is (are) credited here. 

Sketchbook Content
A short summary of the sketchbook's subject matter, including any groups of works to which the drawings in the book relate, as well as other noteworthy facts, e.g., the smallest known sketchbook (RLCR 1483).

Drawings Originating in Sketchbook

The number of drawings matched to the sketchbook and levels of certainty of matches are summarized. If drawings are potential matches to more than one sketchbook, all potential matches are disclosed. Paper characteristics and other criteria are not described; it is implied that they match the sketchbook to the best of our knowledge. We comment on the orientation of drawings since it reflects the orientation of the sketchbook’s use. Drawing dates and content are summarized briefly.

For further details on our sketchbook page-matching methodology see Drawings Formerly in, or Likely Originating in Sketchbook.

Provenance

Provenance is listed in the umbrella record of each sketchbook.

See also: 12. PROVENANCE, 13. EXHIBITIONS, 14. LITERATURE

Sketchbooks: Individual Pages

Title

The drawings in Lichtenstein’s sketchbooks are usually preparatory sketches for known artworks. Their titles thus reflect a finished artwork’s title, followed by "(Study)."

See also: 6. TITLES

Images

In the individual page entries, Primary Images show double spreads of the pages (or single spreads for the rare case when a drawing is found on the adjacent page), rotated to display the correct orientation of the drawing. When viewed from the umbrella record of a sketchbook instead, these images are shown in the orientation of the sketchbook format. Research Images for sketchbook pages illustrate select details that cannot be perceived in the Primary Image (e.g., RLCR 4749.3). In the special case when a drawing is matched to a sketchbook on the basis of linear depressions in a sketchbook page from the pressure of drawing on top of it, a raking light image of the linear depressions is published as a Research Image (e.g., RLCR 3602.5). The record number and title of the matched drawing are given in the image caption.

Date

Dates assigned to the individual page records are based on the year the artist is believed to first conceive an idea, either following the confirmed dates of related finished artworks, or considering the time span over which the artist probably worked on a group of works.

See also: 8. DATES

Media/Support

Indicated are the mediums employed to execute the image on the page. Graphite pencil and colored pencil are the primary media found. The support is "paper" or "ruled paper." For further paper characterization (color, thickness, etc.), consult the sketchbook umbrella record.

Image Dimensions

Image dimensions are only listed when the artist drew a border line around a sketch. For sheet dimensions, see the sketchbook umbrella record.

Marks

Marks on the verso and their location are recorded. These are typically previously assigned record numbers written in graphite pencil. Because marks on the recto are usually visible in a record’s image, those are only transcribed when illegible in the photograph.

Sketchbook Page Number

Most times Lichtenstein drew on the recto of a leaf. Those page numbers are given without any side reference (e.g., "page 5"). The side is indicated only when the verso is used (e.g., "page 5v"), or when both sides are drawn on (e.g., "page 5r" or "page 5v"). 

Drawings Formerly in, or Likely Originating in Sketchbooks

Methodology

All drawings on loose sheets (approximately 1,900) were surveyed for potential sketchbook matches. The authors identified a large number of those drawings as either "formerly in sketchbook" (high certainty), or "likely originating in sketchbook" (lower certainty).

We prioritized physical qualities of the sheets when considering a match, including dimensions, edges, paper structure, thickness, watermarks, paper color and texture as well as any direct evidence of previous binding, such as number and shape of holes from spiral bindings (see Criteria below). Contextual details like date, content and media also factored into the assessment.

The survey relied on notes and snapshots produced during examinations by various researchers over more than two decades. The content available for analysis thus varied piece by piece.

Criteria

The physical qualities of the sheets that served as our criteria for matching were defined and used as follows:

- Dimensions had to be smaller than, or matching the sheet or sketchbook leaf size

- Edges cut, torn and deckle edges were compared. When possible, the spine edge (edge removed from the book) was identified by characteristics like spiral binding holes, lifted fibers from easy-tear perforations, adhesive residue from adhesive bindings and single edges (usually the left long edge) cut irregularly by hand

- Sheet structure identified laid versus wove paper and other unique features of paper formation such as inclusions and distinctive embossed patterns

- Sheet thickness compared numerical measurements taken by researchers by paper gauge in inches. To constitute a match, some difference in thickness (+/- .001 inch) was tolerated, especially for thicker sheets. Thicker sheets are more difficult to keep in plane with a gauge, thus we observed a wider range of measurements (approximately +/- .003 inch) by researchers. In the absence of numerical measurements, verbal descriptions of thickness (e.g. "thick," "thin," "thin board?" [yes, intentional]) were considered. In the absence of any information, the apparent thickness observed in photographs was sometimes considered as a last resort.

- Watermarks: often a strong indication of a match. However, the absence of a watermark didn’t rule out a match. Of the sketchbooks with watermarks, four have watermarks on all pages, two have watermarks on most pages, and four have watermarks only on some pages.

- Paper Color and Texture: For the past several years, Foundation researchers were instructed to use the American Print Council Paper Sample Book (Lunning and Perkinson 1996) as a reference for describing paper color and sometimes texture. Prior to this standard, researchers described paper color and texture subjectively. All color assessments were made under different, sometimes challenging lighting conditions, and at times from behind glass. The drawings themselves have faced decades of diverse storage and display conditions and have thus aged differently. For these reasons, paper color was not considered strong evidence for match-making, and due to limited descriptions of texture, it too was usually found unreliable. An exception is made for when raking light images were provided by the researcher, it was sometimes possible to detect distinctive textures in sheets that helped confirm their match.

"Likely originating in sketchbook"

When we concluded that a sheet was a strong potential, but less certain match to a sketchbook, we indicated our uncertainty by designating the drawing "likely originating in sketchbook."

This designation usually results from the following scenarios:

1) the sheet matches the paper description and fits within the dimensions of more than one sketchbook and is thus linked to both as "likely originating in sketchbook"
2) the sheet was trimmed on multiple sides and though it otherwise matches paper description of a sketchbook, it could in theory have been cut from a larger sheet (note that we usually felt confident in linking as "formerly in sketchbook" when at least one dimension—length or width—was an exact match, in addition to other strong criteria)
3) the notes upon which we relied from early examination(s) were not up to our later standards.

Blank Sketchbooks

During our cataloguing process we found several sketchbooks that are blank, but have stubs, indicating they were used by the artist. We classified these as sketchbook (blank/used). In some cases, removed drawings have been identified based on depressions in the sketchbook pages that match the pencil lines on the loose sheets (high certainty match), and/or matching paper. Future connections with loose drawings may still be made, which is why we included records even for the blank/used sketchbooks for which we have not yet found page matches.

Blank sketchbook records have been described following our usual guidelines, but with the expected gaps due to their nature. When drawings on loose sheets have been matched to a blank sketchbook, the date(s) of the drawing(s) originating in the book are given along with a summary of content.

Appendix

Notes on Lichtenstein’s Sketchbook Manufacturers

New York Central Art Supply (i.e. NY Central)
A New York City based art supply store (1905–2016) with a strong paper and sketchbook program. Although the store did not perform its own papermaking or bookbinding, it had a history of working with local bookbinders and commercial binderies to produce custom-made sketchbooks, sometimes with papers and covering materials that the store provided. When we met with the store manager, David Aldera (employed since 1980), he identified about seven of Lichtenstein’s unlabeled sketchbooks (with full canvas bindings and half "Shannon" marbled paper and leather bindings) as such books, in addition to the Wolf Kahn sketchbooks. The covering materials, text block papers and some endpapers match his description of the materials used. Aldera provided some names of local bookbinders hired in his time (including Sage Reynolds, now Four Hands Design Studio), but ultimately, because New York Central provided some of the same materials to different binders/binderies, we have decided not to pursue these complicated leads. Moreover, since New York Central conceived of the idea for the sketchbooks, we consider them the manufacturer. For brevity, we use "NY Central," rather than "New York Central Art Supply" in the title.

Black Sketchbooks
These were probably distributed by New York Central Art Supply, as confirmed by David Aldera. Two supply catalogues from 1964 and 1973 list nearly identical sketchbooks (sewn bond paper text blocks, black imitation-leather covering material, and equal dimensions). Lichtenstein’s sketchbooks only differ in that they consistently contain 142 pages, whereas the New York Central catalogs advertise 192 and 200 page sketchbooks. This does not rule out the possibility of their distribution, because they may have been sold with 142 pages in other years. Regardless, we do not currently consider New York Central the manufacturer. They were apparently conceived of by another, unknown manufacturer, who likely distributed through New York Central.

Wolf Kahn
The artist proposed to Steven Steinberg, then owner of New York Central, that he produce a spiral-bound sketchbook using Kahn’s preferred Somerset pastel paper (100% cotton), mould-made at St. Cuthbert’s Mill in Wells, England. The Wolf Kahn sketchbook series has been sold for decades in multiple sizes, including (in inches) 4 x 6, 6 x 9, 9 x 12, 11 x 14, 14 x 18, 14 x 22, 22 x 30, 30 x 34, 35 x 46 ¾, and possibly more; and in "cream, radiant white, soft white, and white" colors. Because Wolf Kahn conceived of the idea for the books, his name is used in the title.

Diane & Paul Maurer
Bookbinders and paper artists who were working together at the time of manufacture (1989) of RLCR 3871 in Spring Mills, PA. Diane Maurer purchased her text blocks, previously made from acid-free paper and adhesive-bound. Diane and Paul executed the paper marbling and bound their books without external commission. They sold their sketchbooks through multiple distributors. Because they conceived of the idea for the work, they are considered the manufacturers.

Piazzesi Bookbindery
A paper shop in Venice, Italy, open since 1851 and famous for its hand-printed papers. Today the shop is run by Lavinia Rizzi. The store archive still contains swatches of the exact covering papers that are on Lichtenstein’s sketchbooks. Two of them utilize the hand-printed Piazzesi papers. Two others are covered with papers from other manufacturers, including a Carta Varese paper based on a traditional Remondini pattern. The Piazzesi studio did not manufacture paper itself. Because Piazzesi conceived of the idea for the sketchbooks and sourced the materials for this purpose, it is considered the manufacturer.