Wikipedia, dt.
http://de.wikipedia.org/wiki/Gervase_Markham
Dictionary of National Biography 36 (1885), S. 166-168
http://www.archive.org/stream/dictionaryofnati36stepuoft#page/166
http://en.wikisource.org/wiki/Markham,_Gervase_%28DNB00%29
Encyclopedia of British Writers, 16th, 17th, and 18th Centuries.New York. 2005, S. 257-258
https://books.google.de/books?id=2J7XGzpSCncC&pg=PA257
Johnson, Cuthbert W. The farmer's encyclopaedia. London. 1842, S. 818
https://books.google.com/books?id=pFe9R-w7yH4C&pg=PA815