Gleason, H.A., author
Henry Holt, 1958
Buku Teks
Gleason, H.A., author
Holt, Rinehart and Winston, 1955
Buku Teks
Oxford, England : Oxford University Press
Majalah, Jurnal, Buletin
Barker, Miltos E.
Hongkong : Hongkong University, 1960/1961
Buku Teks
Amsterdam : North-Holland Publishing
Majalah, Jurnal, Buletin