Ignacij Klemenčič (Kamni Potok, 6 February 1853 - Trebnje, 5 September 1901) was a Carniolan physicist of Slovene descent.
Kleene je med drugim napisal "Uvod v metamatematiko" ("Introduction to Metamathematics") 1952 in "Matematična logika" ("Mathematical Logic") 1967.