Google Books Ngram Viewer

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

1800 - 1947 1948 - 1979 1980 - 1984 1985 - 1996 1997 - 2000 viruses English
1800 - 1807 1808 - 1814 1815 - 1858 1859 - 1933 1934 - 2000 viri English

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