QUASI-MEDIAN GRAPHS AND ALGEBRAS

Scattered through the literature various structures occur that general ize median graphs and median algebras: quasi-median graphs, retracts o f Hamming graphs, graphs of finite windex, isotropic media, subdirect products of simplex algebras, certain ternary algebras, and so on. We connect them all up, provide some new generalizations of quasi-median graphs, some new sets of axioms for quasi-median algebras, and some sh orter proofs as well. (C) 1994 John Wiley & Sons, Inc.