Quipper offers free online education. IN Business Agenda. Manila Bulletin.
Cita Chicago (17th ed.)"Quipper Offers Free Online Education. IN Business Agenda." Manila Bulletin .
Cita MLA (9th ed.)"Quipper Offers Free Online Education. IN Business Agenda." Manila Bulletin, .
Atenció: Aquestes cites poden no estar 100% correctes.