Identifying artist signatures and monograms is a challenging task. Within the loops and flourishes, scribbles and scratches, there is hidden a name. Often, the most difficult part is simply determining which letter is which. Thanks to an ever expanding number of texts in the Ingalls Library collection, this research is a bit easier.
The Benezit Dictionary of Artists and Who was Who in American Art both provide example signatures for well known artists. However, the coverage is uneven. These publications devote significantly more space to covering biographical information rather than signatures and marks. Consider it a good place to start.
For researching American artists, begin with the two Castagno guides American Artists: Signatures and Mongrams. The first volume was published in 1990 and contains over 5000 entries. The second volume, recently published, contains another 3500 examples, with less than 5% duplication between the two volumes.
For researching European artists, consult the aptly titled European Artists: Signatures and Monograms, 1800-1990. This text is similar to the American volume, with some 4800 examples. Included are several pages of Cyrillic and Greek signatures, as well as a selection of a number of relevant Chinese and Japanese signatures.
Researchers of Latin American artists will find the Castagno's aptly titled volume Latin American Artists' Signatures and Monograms: Colonial Era to 1996 especially helpful, in that it includes more in depth biography. A comparison of biographical entries between this text and Benezit, provides insight. Wherein the entry for a well known artist, such as Diego Rivera, is much longer in Benezit, the Castagno text contains longer biographies on lesser known artists.
We are fortunate enough to have both of the recent updates of Monogrammlexicon, volume one and two, as well as the 1964 edition. Comparing the original with the recent editions is an interesting study of the evolution of this inexact science. Text in English and German is thoughtful and easy to understand, as is the layout of the book.
The Concise Dictionary of Artists' Signatures by Radway Jackson, in addition to being a quality resource, also provides an interesting essay in its preface on the importance of identifying artist's marks to the amateur collector.
The field grows more specific, with books covering different styles and time periods in art. For coverage of illustration, there is Artists as Illustrators, also by Castagno. Research identifying old masters will be aided by the newly acquired, Old Masters: Signatures and Monograms. I recently used Monograms of Victorian & Edwardian Artists by Peter Nahum and I found it especially compelling, in that it includes the genre or specialty the artist worked within. The two volumes of Belgian Artists' Signatures by Piron are useful in that one needs only a slight understanding of French and Dutch to use them.
Finally, for those signatures that are especially difficult to decipher consult the Artists' Monograms and Indiscernible Signatures. As with the previous Castagno volumes there is an older text, printed in 1991, and a newer text, printed recently.