US patent 4563452, Jose M. Ribalta-Baro and Jordi F. Rigola-Constansa, "Benzothiazine derivatives and their applications as medicinal products or as synthesis intermediates for medicinal products", issued 1992-07-21, assigned to Laboratorios del Dr Esteve SA
nih.gov
pubmed.ncbi.nlm.nih.gov
Jané F, Rodríguez de la Serna A (1991). "Droxicam: a pharmacological and clinical review of a new NSAID". European Journal of Rheumatology and Inflammation. 11 (4): 3–9. PMID1365488.