(1980), “"The International Directory of Portuguese Studies, including scholars, students and institutions concerned with all aspects of the study, past and present, os Portugal and of Portuguese-speaking Africa and Asia", por Douglas L. Wheeler”, Fundação Mário Soares e Maria Barroso / António Rita-Ferreira, Disponível em: https://casacomum.org/visualizador?cota=10468.002 (consultado em 2026-08-18)

"The International Directory of Portuguese Studies, including scholars, students and institutions concerned with all aspects of the study, past and present, os Portugal and of Portuguese-speaking Africa and Asia", por Douglas L. Wheeler. Fundação Mário Soares e Maria Barroso, António Rita-Ferreira, 1980. Cota: 10468.002. [Consult. 18 ago. 2026]. Disponível em: https://casacomum.org/visualizador?cota=10468.002

(1980). "The International Directory of Portuguese Studies, including scholars, students and institutions concerned with all aspects of the study, past and present, os Portugal and of Portuguese-speaking Africa and Asia", por Douglas L. Wheeler. Fundação Mário Soares e Maria Barroso, António Rita-Ferreira. https://casacomum.org/visualizador?cota=10468.002

“"The International Directory of Portuguese Studies, including scholars, students and institutions concerned with all aspects of the study, past and present, os Portugal and of Portuguese-speaking Africa and Asia", por Douglas L. Wheeler,” 1980, António Rita-Ferreira, Fundação Mário Soares e Maria Barroso. https://casacomum.org/visualizador?cota=10468.002.