2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100489We examine special extended spin S=1/2 fermionic and hard core bosonic t-J_{z} models and find exact ground states. Some of these models display an exponentially large degeneracy with diagonal stripe like patterns.6 pages, 2 figuresStrongly Correlated ElectronsSuperconductivityExact ground states of extended t-J_{z} models on a square latticetext