George Albert Boulenger,
Snakes of Europe — Preface
“ Whenever I have had to compile, and to trespass on ground that is not my own, I have been careful to draw only from the writings of the most trustworthy authorities. The descriptions of the species are based on the collection in the British Museum, which has been considerably increased since the publication of the Catalogue of Snakes (1893-1896) . ”
