United Nations, 1983
Buku Teks
Popescu-Zeletin, Radu, editor
[, Springer], 2012
eBooks
Edited by Ben G. Goedegebuure; Humberto R. Arango Sales; Gilberto Sotolongo Aguilar
Elsevier, 1991
Buku Teks
Gonzalo Mejia, editor, Nubia Velasco, editor
[, Springer], 2012
eBooks
editors by G. Russell Pipe; A.A.M. Veenhuis
North-Holland Publishing Company, 1975
Buku Teks