Lasker introduced the practice of demanding that the challenger should provide the whole of the purse, and his successors followed his example up to World War II. This requirement makes arranging world championship matches more difficult, for example: Marshall challenged Lasker in 1904 but could not raise the money until 1907; in 1911 Lasker and Rubinstein agreed in principle to a world championship match, but this was never played as Rubinstein could not raise the money. In the early 1920s, Alekhine, Rubinstein and Nimzowitsch all challenged Capablanca, but only Alekhine was able to raise the US$10,000 that Capablanca demanded, and not until 1927. Attempts to form an international chess federation were made at the time of the 1914 St. Petersburg, 1914 Mannheim and 1920 Gothenburg Tournaments. On 20 July 1924 the participants at the Paris tournament founded FIDE as a kind of players' union. FIDE's congresses in 1925 and 1926 expressed a desire to become involved in managing the world championship. FIDE was largely happy with the "London Rules", but claimed that the requirement for a purse of $10,000 was impracticable and called upon Capablanca to come to an agreement with the leading masters to revise the Rules. In 1926 FIDE decided in principle to create a parallel title of "Champion of FIDE" and, in 1928, adopted the forthcoming 1928 Bogoljubow–Euwe match (won by Bogoljubow) as being for the "FIDE championship". Alekhine agreed to place future matches for the world title under the auspices of FIDE, except that he would only play Capablanca under the same conditions that governed their match in 1927. Although FIDE wished to set up a "unification" match between Alekhine and Bogoljubow, it made little progress and the title "Champion of FIDE" quietly vanished after Alekhine won the 1929 world championship match that he and Bogoljubow themselves arranged. While negotiating his 1937 World Championship rematch with Alekhine, Euwe proposed that if he retained the title FIDE should manage the nomination of future challengers and the conduct of championship matches. FIDE had been trying since 1935 to introduce rules on how to select challengers, and its various proposals favored selection by some sort of committee. While they were debating procedures in 1937 and Alekhine and Euwe were preparing for their rematch later that year, the Royal Dutch Chess Federation proposed that a super-tournament (AVRO) of ex-champions and rising stars should be held to select the next challenger.