Terms for subject Mathematics containing two fold

English	Russian
fold in two	складывать вдвое
fold in two	сложить вдвое
the purpose of this paper is two-fold: to introduce ... and to exhibit	цель данной книги двоякая
two fold	два раза
two fold	в два раза больше
two-fold	двоякий
two-fold coincidence	двукратное совпадение
two-fold covering	двойное накрытие
two-fold series	двойной ряд
two-fold torus	двойной тор