@article{article_102780, title={Effects of gender , cognitive development and socioeconomic status on physics achievement}, journal={Hacettepe Üniversitesi Eğitim Fakültesi Dergisi}, volume={15}, year={1999}, author={Yıldırım, Ufuk and Eryılmaz, Ali}, number={15}, publisher={Hacettepe Üniversitesi}