Spellman, B. J. (1960). Laboratory exercises in physical geography (Revised ed.). St. Norbert College.
Chicago-viite (17. p.)Spellman, Boniface J. Laboratory Exercises in Physical Geography. Revised ed. [De Pere, Wis.]: St. Norbert College, 1960.
MLA-viite (8. p.)Spellman, Boniface J. Laboratory Exercises in Physical Geography. Revised ed. St. Norbert College, 1960.
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