APA

SAGER R. J., . (1998). Modern Rarth Science. london: holt, rinehart and winston.

Chicago

SAGER ROBERT J, . 1998. Modern Rarth Science. london: holt, rinehart and winston.

Harvard

SAGER R. J., . (1998). Modern Rarth Science. london: holt, rinehart and winston.

MLA

SAGER ROBERT J, . Modern Rarth Science. london: holt, rinehart and winston. 1998.