Pieper, F.C.
SISCIS: Subject index to sources of comparative international statistics
CBD Research, 1978
 Buku Teks
Sources of unofficial UK statistics
compiled by David Mort
Gower, 1990
 Buku Referensi
Sources of unofficial UK statistics
compiled by David Mort and Leona Siddall
Gower, 1985
 Buku Referensi
Thirlway, Hugh
The sources of international law
Oxford University Press, 2014
 Buku Teks
International trade statistics
edited by R.G.D. Allen and J. Edward Ely
John Wiley & Sons, 1953
 Buku Teks