public static function retriveByStudentCareerSchoolYearAndPeriod($student_career_school_year, $period)
 {
     $c = new Criteria();
     $c->add(StudentCareerSchoolYearConductPeer::STUDENT_CAREER_SCHOOL_YEAR_ID, $student_career_school_year->getId());
     $c->add(StudentCareerSchoolYearConductPeer::CAREER_SCHOOL_YEAR_PERIOD_ID, $period->getId());
     return StudentCareerSchoolYearConductPeer::doSelectOne($c);
 }