http://lewisandclarkjournals.unl.edu/namesindex/journals.php?id=lc.1804-12-16&key=Gass,+Patrick (http://lewisandclarkjournals.unl.edu/namesindex/journals.php?id=lc.1804-12-16&key=Gass,+Patrick)
http://www.northwestjournal.ca/XI1.htm (http://www.northwestjournal.ca/XI1.htm)
http://www.lewis-clark.org/content/content-article.asp?ArticleID=1559 (http://www.lewis-clark.org/content/content-article.asp?ArticleID=1559)
http://www.hbc.com/hbcheritage/history/people/women/isobelgunn.asp (http://www.hbc.com/hbcheritage/history/people/women/isobelgunn.asp)
http://www.nps.gov/history/history/online_books/lewisandclark/intro27.htm (http://www.nps.gov/history/history/online_books/lewisandclark/intro27.htm)
http://www.history.army.mil/LC/The%20People/Frontier.htm (http://www.history.army.mil/LC/The%20People/Frontier.htm)