"Hidetoshi NishimoriKenn KuboYukiyasu OzekiYasuhiro TomitaTatsuya Kishi,Hidetoshi Nishimori,Kenn Kubo,Yukiyasu Ozeki,Yasuhiro Tomita,Tatsuya Kishi","Long-range order in the XXZ model",,"Journal of Statistical Physics",,"Volume 55","  Issue 1-2","pp. 259-277",1989,Apr.