1 : REQUIRE , OBLIGE <may be called upon to do several jobs>
2 : to make a demand on : depend on <universities are called upon to produce trained professionals>
1 : REQUIRE , OBLIGE <may be called upon to do several jobs>
2 : to make a demand on : depend on <universities are called upon to produce trained professionals>
Merriam Webster Collegiate English Dictionary. Merriam Webster - Энциклопедический словарь английского языка. 2012