| N. Denholm-Young |
Walter of Henley and other Treatises on Estate Management and Accounting, by Dorothea Oschinsky |
|
42/1, p. 57 |
| N. Denholm-Young |
A concise economic history of Great Britain from the earliest times to A. D. 1750, by John Clapham |
|
19/, p. 84 |