1:
file:///C:/Users/Osama%20Tariq/Downloads/iSTEAMPAPER-RESEARCHGATE.pdf
2: https://www.idosi.org/ejas/7(1)15/6.pdf 3: http://www.academia.edu/19600558/online_clearance_system 4: https://www.pdfcoke.com/document/349833751/wolkite-university-clearance-system 5: http://www.academia.edu/9410384/DESIGN_AND_IMPLEMENTATION_OF_ONLINE_STUDENT_CLEARAN CE_SYSTEM 6: https://www.academia.edu/12980935/ONLINE_STUDENT_CLEARANCE_SYSTEM_CASE_STUDY_CUR_CA THOLIC_UNIVERSITY_OF_RWANDA?auto=download 7.
https://crs.upd.edu.ph/downloads/ClearanceMechanics.pdf