Query to to find the Employee Supervisor name

SELECT papf1.full_name            supervisor_nameFrom apps.per_all_people_f papf,
       apps.per_all_assignments_f paaf,
       apps.per_all_people_f      papf1

 WHERE papf.person_id = paaf.person_idAND paaf.primary_flag = ‘Y’AND
 paaf.assignment_type = 'E'AND
 paaf.supervisor_id = papf1.person_idAND
 papf1.current_employee_flag = 'Y'AND
 papf.business_group_id = paaf.business_group_idAND
 SYSDATE BETWEEN papf.effective_start_date and
       papf.effective_end_dateAND
 SYSDATE BETWEEN paaf.effective_start_date AND
       paaf.effective_end_dateAND
 SYSDATE BETWEEN papf1.effective_start_date AND
       papf1.effective_end_dateAND
 papf.employee_number = :p_emp_number;