Marthese Azzopardi and  Liberato Camilleri,  Study Habits and Level of Difficulty Encountered by Maltese Students Studying Biology Advanced Level Topics.   journal   = {International Journal of Educational and Pedagogical Sciences}, [online]. World Academy of Science, Engineering and Technology.
    May 2018, vol. 138(6). 723 - 728
    [viewed 05 December 2021]. Available from: https://publications.waset.org/pdf/10009098.