Novaliyosi, N., B. Tola, and W. Rahayu. “TRENDS OF MATHEMATICAL LOGICAL THINKING ABILITYTHROUGH THE CRA (CONCRETE-REPRESENTATIONAL-ABSTRACT) APPROACHWITH PORTFOLIO ASSESSMENT”. IJER - INDONESIAN JOURNAL OF EDUCATIONAL REVIEW, Vol. 6, no. 2, Jan. 2020, http://103.8.12.212:33180/unj/index.php/ijer/article/view/14077.