http://repository.uhamka.ac.id/id/eprint/11155/ Dan Dan, Mugisidi http://repository.uhamka.ac.id/id/eprint/11155/1/turnitin%20Performance%20Improvement%20of%20a%20Forced%20Draught%20Cooling%20Tower%20Using%20a%20Vortex%20Generator.pdf Unduh!