Merck Manual of Diagnosis and Therapy

The Merck Manual of Diagnosis and Therapy (often referred to simply as The Merck Manual) is one of the world's most widely used medical textbooks. In 1899 it was first published under the name Merck's Manual of the Materia Medica. The current version is the 2006 18th edition (ISBN 0-911910-18-2). The same editors produce The Merck Manual -- Second Home Edition, which is a lay version of the content. The text is freely available from the website of its publisher, the United States pharmaceutical company Merck & Co., Inc. Also go to The Merck Manuals