Gupta, O. P. Weedy Aquatic Plants: Their utility, menace and management.
Chicago Style (17th ed.) ZitazioaGupta, O. P.1933-. Weedy Aquatic Plants: Their Utility, Menace and Management.
MLA (9th ed.) ZitazioaGupta, O. P.1933-. Weedy Aquatic Plants: Their Utility, Menace and Management.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.