Google Books Ngram Viewer

Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
Search in Google Books:

1940 - 1944 1945 1946 - 1956 1957 - 1973 1974 - 1980 occupation of the baltic states English
1940 - 1941 1942 - 1952 1953 1954 - 1969 1970 - 1975 occupation of the baltic republics English

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