Google Books Ngram Viewer

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

1800 - 1960 1961 - 1994 1995 - 1996 1997 - 1998 1999 - 2000 friedrich hayek English
1800 - 1920 1921 - 1977 1978 - 1984 1985 - 1991 1992 - 2000 karl marx English

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