Busra, M., Yuliarni Syafrita and Hendra Permana 2021. Relationship of Serum Tau Levels with Cognitive Functions and Factors Affecting The Cognitive Function Decrease in Parkinson’s Disease Patients. Bioscientia Medicina : Journal of Biomedicine and Translational Research. 5, 6 (Mar. 2021), 513-519. DOI:https://doi.org/10.32539/bsm.v5i6.317.