Google Books Ngram Viewer

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

1800 - 1951 1952 - 1990 1991 1992 - 1995 1996 - 2000 copyright clause English
1800 - 1989 1990 - 1995 1996 intellectual property clause English
1800 - 1939 1940 - 1955 1956 1957 - 1993 1994 - 2000 patent and copyright clause English
1800 - 1893 1894 - 1994 1995 1996 - 1999 2000 patent clause English
1800 - 1991 1992 1993 1994 copyright and patent clause English

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