In 1926 Lasker wrote "Lehrbuch des Schachspiels", which he re-wrote in English in 1927 as "Lasker's Manual of Chess". He also wrote books on other games of mental skill: "Encyclopedia of games" (1929) and "Das verständige Kartenspiel" (1929); English translation in the same year. Both these books posed a problem in the mathematical analysis of card games. "Brettspiele der Völker" ("Board games of the nations" 1931) had 30 pages about Go and a section about a game he had invented in 1911, "Lasca". "Das Bridgespiel" "The Game of Bridge" was published in 1931. Lasker became an expert bridge player, representing Germany at international events in the early 1930s, and a registered teacher of the Culbertson system. 