http://repository.uhamka.ac.id/id/eprint/13621/
Validity of critical thinking skills instrument on prospective Mathematics teachers
Faradillah, Ayu
http://repository.uhamka.ac.id/id/eprint/13621/1/Jurnal%20Penelitian%20dan%20Evaluasi%20Pendidikan%20%28Sabila%29.pdf