i am encountering a Linker Error: Undefined reference in my program under DEV c++ it involves usage of the NTL class of header files. i have downloaded those files and have every header file existing in the required forlder of NTL. but still there are issues concerning the reference. i have tried including that folder at every possible location of BIN, include, LIB. the folder is also included within tht folder where my program is stationed. yet there are reference errors cropping up. [Linker error] undefined reference to `NTL::ZZ_p::ZZ_p()' [Linker error] undefined reference to `NTL::sub(NTL::ZZ&, NTL::ZZ const&, long)' there are around 230 of these errors and all asoosciated with NTL class only. can somebody plz suggest wat is going wrong.