List of acceptable online sources (this is in no way exhaustive):
a. American Yawp: http://www.americanyawp.com/
c. Digital History: http://www.digitalhistory.uh.edu/
d. Gilder Lehrman: https://www.gilderlehrman.org/
e. Library of Congress: https://www.loc.gov/collections/ and https://www.loc.gov/rr/program/bib/ourdocs/index.html
f. National Archives: https://www.archives.gov/education/research/primary-sources
g. History Matters: http://historymatters.gmu.edu/browse/manypasts/%3Cbr%20/%3E
h. TeacherServe: http://nationalhumanitiescenter.org/tserve/