Spalding, M. W. (1950). A guide for nature teaching in camps, schools and homes. Madison College.
Lua i Stíl Chicago (17ú heag.)Spalding, Muad W. A Guide for Nature Teaching in Camps, Schools and Homes. Madison College, 1950.
Lua MLA (9ú heag.)Spalding, Muad W. A Guide for Nature Teaching in Camps, Schools and Homes. Madison College, 1950.
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