Artikel Jurnal
Fokker, Abraham Anthony, 1862-1927
Pradnja Paramita, 1972
Buku Teks
Ellis, Nick C., author
Wiley, 2016
Buku Teks
Giorgi, Alessandra
Cambridge University Press , 1991
Buku Teks
Warburton, G.B. (Geoffrey Barratt), 1924-, author
Pergamon Press, 1976
Buku Teks