Weisstein, Eric W. "Differential Operator." From MathWorld--A Wolfram Web Resource. "Differential Operator". Archived from the original on 2016-01-21. Retrieved 2016-02-07.
Weisstein, Eric W. "Repeated Integral." From MathWorld--A Wolfram Web Resource. "Repeated Integral". Archived from the original on 2016-02-01. Retrieved 2016-02-07.
Weisstein, Eric W. "Differential Operator." From MathWorld--A Wolfram Web Resource. "Differential Operator". Archived from the original on 2016-01-21. Retrieved 2016-02-07.
Weisstein, Eric W. "Repeated Integral." From MathWorld--A Wolfram Web Resource. "Repeated Integral". Archived from the original on 2016-02-01. Retrieved 2016-02-07.
Weisstein, Eric W. "Overdot." From MathWorld--A Wolfram Web Resource. "Overdot". Archived from the original on 2015-09-05. Retrieved 2016-02-05.
Weisstein, Eric W. "Double Dot." From MathWorld--A Wolfram Web Resource. "Double Dot". Archived from the original on 2016-03-03. Retrieved 2016-02-05.
worldcat.org
search.worldcat.org
Morris, Carla C. (2015-07-28). Fundamentals of calculus. Stark, Robert M., 1930-2017. Hoboken, New Jersey. ISBN9781119015314. OCLC893974565.{{cite book}}: CS1 maint: location missing publisher (link)