The Bailey mod 9 identities are a set of three Rogers-Ramanujan-like identities appearing as equations (1.6), (1.8), and (1.7) on p. 422 of Bailey
(1947) given by

Unfortunately, Bailey used non-standard (and essentially unreadable) notation in the paper where these identities first appeared. All three of these identities appear in the list of Slater (1952) as equations (42), (41), and (40) in that order. However, all three contain misprints.

In one sense, these identities are the next logical step in the following sequence:

3. The (sort of) four Bailey mod 9 identities (triple product on mod 9 over ).

Here, "sort of" refers to the fact that between and , there is an "identity" in which the product
side contains ,
so the identity reduces to and therefore is not listed.

Bailey, W. N. "Some Identities in Combinatory Analysis." Proc. London Math. Soc.49, 421-435, 1947.Mc
Laughlin, J.; Sills, A. V.; and Zimmer, P. "Dynamic Survey DS15: Rogers-Ramanujan-Slater
Type Identities." Electronic J. Combinatorics, DS15, 1-59, May 31, 2008.
http://www.combinatorics.org/Surveys/ds15.pdf.Slater,
L. J. "Further Identities of the Rogers-Ramanujan Type." Proc.
London Math. Soc. Ser. 254, 147-167, 1952.Sloane, N. J. A.
Sequences A104467, A104468,
and A104469 in "The On-Line Encyclopedia
of Integer Sequences."