Parents' Magazine's Cultural Institute, 1965
Buku Referensi
Busch, Moel F.
American Heritage Pub. Co., 1972
Buku Teks SO
edited by M.A.P. Meilink-Roelofsz, M.E. van Opstall, G.J. Schutte
Foris, 1988
Buku Teks SO
edited by C.D. Cowan and O.W. Wolters
Cornell University Press, 1976
Buku Teks SO
edited by S.L. Goldberg and F.B. Smith
Cambridge University Press, 1988
Buku Teks SO