J.R. Landon 
Booker Tropical Soil Manual [EPUB ebook] 
A Handbook for Soil Survey and Agricultural Land Evaluation in the Tropics and Subtropics

First published in 1991. This is a more portable version of the Booker Tropical Soil Manual, in which the format (and weight) of the first edition have been reduced whilst retaining as much as possible of the original clarity. It also includes new content and appendices that cover the revised FAO publications on soil classification and on water quality for agriculture.