Decidable Varieties of Hoops. - Stanley Burris; Isabel M. A. Ferreirim (Reports Math. Log., 1994)

A Short Note on Hoops and Continuous {t}-norms. - Isabel M. A. Ferreirim (Reports Math. Log., 2000)

Errata to RML: 34 A Short Note on Hoops and Continuous t-norms. - Isabel M. A. Ferreirim (Reports Math. Log., 2002)

Basic Hoops: an Algebraic Study of Continuous t -norms. - Paolo Aglianò; Isabel M. A. Ferreirim; Franco Montagna (Stud Logica, 2007)