Ascribed to
Means a traditional or previously proposed attribution, typically by way of an inscription on the drawing or its mount, has been retained, generally for want of a better alternative, but with little assurance that it is correct.

Attributed to
Means that, even if the attribution is based on stylistic evidence alone, it is correct in the author’s opinion.

Circle of and follower of indicate the relative proximity, in decreasing order, of an anonymous work to that of a known master.

Composition
The arrangement of the individual elements within a work of art so as to form a unified whole; also used to refer to a work of art, music, or literature, or its structure or organization.

Draftsman/ Draughtsman
A person who draws plans or designs, often of structures to be built; a person who draws skillfully, especially an artist. “Draughtsman” is the British variation of “Draftsman”.

Foxing
Small, dark brown spots on the paper which develop over time. There are many possible chemical and microbiological origins of foxing stains, but most are caused by mold or other fungi growth on the surface of the paper.

Laid Paper
Paper made by pulp being poured into a mold made of a wooden framework with wire mesh on the bottom. Laid paper is made by hand and the size of the sheets is limited by the size of the mold. Laid paper can be recognized by the pattern impressed into the paper by the wire mesh. Papermakers can weave designs into the mesh with wire to create watermarks.

Prepared Paper
Paper that has been coated with a thin layer of primer or gesso.

Provenance
The chronology of the ownership, custody or location of a historical object.

Recto
The front of a work on paper. Derived from the Latin term “recto folio,” referring to the right-hand page of an open book.

Sketch
A rough or unfinished version of any creative work, often made to assist in the completion of a more finished work.

Squaring
A technique to facilitate the enlargement or reduction of a design. A grid containing an equal number of squares is ruled on the original drawing and on the surface destined for the enlarged design, then transferred square by square.

Study
A drawing or painting executed in preparation for a finished piece, used as visual notes  in order to better understand compositional arrangement, subject rendering, light, form and/ or perspective.

Verso
The back of a work on paper. Derived from the Latin term “verso folio,” referring to the left-hand (turned) page of an open book.

Watermark
A device used by paper manufacturers made of wire and sewn onto the papermaking mold, leaving an impression on the paper by making it thinner and therefore more translucent. These are often used to distinguish papermaking regions or towns, as well as individual paper mills.

Workshop of or Studio of
Means that, in the author’s opinion, the work was executed by a pupil or assistant under a known master’s supervision.

Wove Paper
Paper made with a revolving roller covered with wires so woven as to produce no fine lines running across the grain. The result is a smooth, uniform surface. This technique was invented in England in the mid-18th century and overtook laid paper in popularity during the 19th century. Today, wove paper accounts for more than 99% of all paper produced.

As you read through the individual entries, you often will find abbreviations for the following additional sources:

Alasko, Richard-Raymond. “Appraisal Report for The Sonnenshein Collection of Fifty-eight Old Master Drawings.” Unpublished Document. Chicago: The Alasko Company, 1997. (Alasko)

Heawood, Edward. Watermarks: Mainly of the 17^th and 18^th Centuries, Vol. I, Monumenta  Chartae Papyraceae: Historiam Illustrantia. 2^nd ed. Edited by E.J. Labarre. Hilversum: The Paper Publications Society, 1957. (Heawood)

Lugt, Frits. Les marques de collections de dessins & d’estampe  (Amsterdam,  1921 and The Hague, 1956), Online Digital Database,  http://www.marquesdecollections.fr (Lugt)