APA-referens (7:e uppl.)
Walford, N. (2011). Practical statistics for geographers and earth scientists. Wiley-Blackwell.
Chicago-referens (17:e uppl.)
Walford, Nigel. Practical Statistics for Geographers and Earth Scientists. Chichester, West Sussex, UK: Wiley-Blackwell, 2011.
MLA-referens (9:e uppl.)
Walford, Nigel. Practical Statistics for Geographers and Earth Scientists. Wiley-Blackwell, 2011.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.