General view of the agriculture of the county of Hertford with observations on the means of its improvement - Walker, D. (Printed by W. Bulmer, 1795)
"Drawn up for the consideration of the Board of Agriculture and Internal Improvement". - Goldsmiths'-Kress no. 16265. - OCLC, 21967221. - Reproduction of original from Goldsmiths' Library, University of London