(1940). Nature recreation: Group guidance for the out-of-doors / by William ("Cap'n Bill") Gould Vinal.
Chicago-viite (17. p.)Nature Recreation: Group Guidance for the Out-of-doors / by William ("Cap'n Bill") Gould Vinal. 1940.
MLA-viite (9. p.)Nature Recreation: Group Guidance for the Out-of-doors / by William ("Cap'n Bill") Gould Vinal. 1940.
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