Leifer, Michael. (1968). The Philippine claim to Sabah / Michael Leifer. Switzerland :: Interdocumentation Company,.
Leifer, Michael. The Philippine claim to Sabah / Michael Leifer. Switzerland :: Interdocumentation Company,, 1968
Leifer, Michael. The Philippine claim to Sabah / Michael Leifer. Switzerland :: Interdocumentation Company,, 1968.