J.E. KAUFMANN is a retired public school teacher and has written several books on fortifications.He is founder of SITE O, an international research group consisting of enthusiasts and experts in the field of fortifications.
CLAYTON DONNELL recently retired from the U.S. Air Force. He spent several years in Europe doing field research on the Maginot Line and other French fortification systems. In 1996 he created one of the first internet sites in the world devoted to the Maginot line. He is an avid military historian and is especially versed in the period of the European conflicts from 1870 to 1945.

This selected bibliography on modern European fortifications, from 1850 to 1950, provides a selection of the most important books and articles written on this topic. The work covers regions and countries and includes many sources on such popular topics such as the Maginot Line along with lesser known fortifications such as the Salpa Line and the Swiss National Redoubt. References for the fortifications that appear cover everything from the Iberian Peninsula to the Soviet Union and from Scandinavia to the Mediterranean countries.
This work includes not only American and English, but also non-English publications. This source features books and articles done in the nineteenth and twentieth century ending in December 2000. Each contributor is a member of SITE O, an international fortifications research group. In addition to helpful annotations, each chapter includes summaries on the fortifications. Also features a multi-lingual glossary and reference maps.