. .. , 1920 , ( 1924 - ) . " " . , " " , " " . . - -, . , . , . , . , . , . , . . .. , .. , .. , . .; .. , . . ; . . . 1930 . . .

"" (2- 1934), "" (1935), "ʸ-" . (1937; , 1941). 1930-40- . . , . . , . , . , . , . , . , . ; . ; : . , . , . ; , . . 1938 . 1940 " " . , "" . (1939), " " (1942), "" . . (1945; , 1946) . 1950-60- . . , . , . , . , . , . , . ; . ; . . - "" (1953), "" . (1957); - "" . (1950; , 1952), " " (1952), " " (1960) . ," " . (1962), "" . (1965), " " . (1969).

.: ., , ., 1931.; ., " " "ʸ-", .: , .- ., 1938; ., , .: , . 3, , 1950; ., . . , , 1958; . ., . . .. , ., 1959; ., , , 1968.

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