APA
"United Nations E. C. F. E., "United Nations E. C. F. E., . (1993). Directory of chemical producers. New: York United Nations U S A.
Chicago
"United Nations Economic Commission For Europe", "United Nations Economic Commission For Europe", . 1993. Directory of chemical producers. New: York United Nations U S A.
Harvard
"United Nations E. C. F. E., "United Nations E. C. F. E., . (1993). Directory of chemical producers. New: York United Nations U S A.
MLA
"United Nations Economic Commission For Europe", "United Nations Economic Commission For Europe", . Directory of chemical producers. New: York United Nations U S A. 1993.
