Dean Allen of Textism writes about Jan Tschichold and his tenure at Penguin Books. Actually, the post is mostly about Penguin Books, but he spends some time discussing Tschichold's transformation of Penguin Books and how his standards guidelines set the tone for the printing of their books for decades.

Allen's post reminds me that Tschichold is one of those designers from the Bauhaus era who is not heard about much in design history. We learn about him and his contributions - predominantly around typography - but he isn't brought up over and over again like the Herbert Bayer's or other more well known designer's of the day. I have often wondered why - his work was intense and quite elegant, even when he cast off the modernist, international style and changed his way of thinking. Perhaps it is because many other designers had a longer time in the spotlight or a larger body of work? Maybe it's an American thing.

Information about Tschichold is not abundant on the web and much of it is from font houses because of the fact that Tschichold designed the face Sabon.

Here are a few of the better sites:
Frostdigital
Linotype: Font Store
Inventory of the Jan and Edith Tschichold Papers | 1899-1979 | Getty Research Institute

Related Books:
The New Typography: A Handbook for Modern Designers by Jan Tschichold. This book is a classic if you are interested in studying about the modernist international style of typography as practiced by the Bauhaus designers.
Jan Tschichold: A Life in Typography by Ruari McLean. About the designer and his work and cultural influences.