Include sites that are about mathematicians, who work in the field of calculus.
Gottfried Wilhelm Von Leibniz lived from 1646 and died in 1716. He was born in Leipzig, Prussia and died in Hannover, Germany.
He was considered by most people to be have independently discovered calculus concepts, along with Sir Isaac Newton.
He was also famous as a philosopher and logician. He's credited with making the first mechanical calculator.