D. Hendriati, E. Effendy, M. M. Amin, V. Camellia, and M. S. Husada, “Brain-Derived Neurotropic Factor Serum Level and Severity Symptom of Bataknese Male Patients with Schizophrenia in North Sumatera, Indonesia”, Open Access Maced J Med Sci, vol. 7, no. 12, pp. 1957–1961, Jul. 2019.