Here are some of his notable works:
Books:
* "Blackmar-Diemer Gambit: A Complete Guide to the Attacking System" (1947): A comprehensive and influential guide to the Blackmar-Diemer Gambit, a popular chess opening.
* "Modern Chess Openings" (1952): A highly acclaimed book that provides a detailed analysis of various chess openings, including the King's Gambit, Queen's Gambit, and various Sicilian variations.
* "The King's Gambit" (1956): A dedicated volume exploring the King's Gambit, a bold opening for White.
* "The Queen's Gambit Declined" (1959): A detailed analysis of the Queen's Gambit Declined, a popular defense for Black.
* "Chess Problems: An Elementary Textbook" (1962): A guide to chess problems for beginners.
* "Endgames of Kings and Pawns" (1964): A book focused on endgames involving only kings and pawns.
* "Chess for Beginners" (1967): A basic introduction to the game of chess.
* "The Modern Sicilian" (1973): A volume focusing on the Sicilian Defense, one of the most popular openings for Black.
Mattfeld also wrote numerous articles for chess magazines and journals, contributing to the understanding and development of chess theory. He was a respected chess expert and author, and his works remain valuable resources for chess players of all levels.