Bibliography of American Literature (commonly abbreviated as BAL in descriptions) is the quintessential reference work for any student of american literature. BAL was originally published in 9 volumes by the Bibliographical Society of America by Yale University Press between 1955 and 1991 with Jacob Blanck as it's lead editor and later finished by Michael Winthrop and Virginia L. Smyers it provides descriptive bibliographic reference for more than 40,000 works from over 300 authors including physical characteristics of different editions of each work.
While not necessarily considered collectible unto itself, BAL is indispensable as a reference to any collector or dealer in american literature and is often cited in descriptive bibliographies. While it is now available online from a variety of sources by subscription, it can also be purchased in print, either in full or by volume.
A common bibliographic citation for BAL might appear something like BAL 6934, the number indicating which entry is referenced.
A reprint edition of BAL from Oak Knoll Press in 2003 is pictured below: