APA
(1990). Use of artificial tracers in hydrology. [s.l.]: [s.n.].
Chicago
1990. Use of artificial tracers in hydrology. [s.l.]: [s.n.].
Harvard
(1990). Use of artificial tracers in hydrology. [s.l.]: [s.n.].
MLA
Use of artificial tracers in hydrology. [s.l.]: [s.n.]. 1990.