Jabarkan Lihat juga dari Protokol Madrid 1885 dalam bahasa melayu

Leigh R. Wright. Historical Notes on the North Borneo Dispute. The Journal of Asian Studies, Vol. 25, No. 3 (May, 1966), pp. 471–484.

Leigh R. Wright. The Origins of British Borneo. Modern Asian Studies, Vol. 10, No. 1 (1976), pp. 149–154

Leigh R. Wright. The Anglo-Spanish-German Treaty of 1885: A Step in the Development of British Hegemony in North Borneo. Australian Journal of Politics & History 18 (1), 62–75