University of the Philippines System. National Center for Transportation Studies. National Center for Transportation Studies. The Center.
Čikaški stil citiranja (17. izdanje)University of the Philippines System. National Center for Transportation Studies. National Center for Transportation Studies. Quezon City: The Center.
MLA način citiranja (9. izdanje)University of the Philippines System. National Center for Transportation Studies. National Center for Transportation Studies. The Center.
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