Simple Variational Wave Functions for Two-Dimensional Heisenberg Spin- 1 2 Antiferromagnets

Authors: 

David A. Huse and Veit Elser,

Phys. Rev. Lett. 60, 2531-2534 (1988)

http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.60.2531