"A small dual-automorphic lattice with no involutory dual automorphism"
K. Rustan M. Leino and Lyle Ramshaw
Note #1997-008. May 27, 1997. 4 pages

An exercise in Garrett Birkhoff's renowned book on lattice
theory asks for a lattice with 18 elements and of length 5 that has
a dual automorphism, but no involutory dual automorphism.  This note
constructs a smaller lattice, 15 elements and length 4, with the
same property.