aw-d is the set of integer m-tuples (a1 ☺ l **t ",) with o 5 al < .*. < am 5 n , ordered by a < b when ai 5 bi for all i . w-s R. Stanley conjectured that L(m,n) is a symmetric chain order for all (m,n) . We verify this by construction for m = 4 . Research supported in part by NSF grant MCS 77-23738 and Office of Naval Research contract ~00014~76-c-0688. Reproduction in whole or in part is perm...