Dr. Eckehard Pfeifer is a mathematician from Dresden. He works as a freelance software developer, consultant, and trainer for Microsoft Office. He is a Microsoft Certified Software Developer (MCSD) for .NET, and focuses primarily on the Office environment. He writes for various publications, and is a co-author of several books.
"Not only is the format of large number of functions mentioned but in-depth examples are subsequently provided. The entire range of functions starting from date and time, text and data, logical and include latest features like power-pivot are explained in details. The book is highly recommended right from the beginner to the advanced user of Microsoft Excel."
--Ganadeva Bandyopadhyay, Blogcritics Books