Philippines Department of Tourism Bureau of Special Services & Philippines. (1992). Rules and regulations to govern the accreditation of travel and tour services. Bureau of Special Services, Department of Tourism.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Philippines Department of Tourism Bureau of Special Services و Philippines. Rules and Regulations to Govern the Accreditation of Travel and Tour Services. [Manila]: Bureau of Special Services, Department of Tourism, 1992.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Philippines Department of Tourism Bureau of Special Services و Philippines. Rules and Regulations to Govern the Accreditation of Travel and Tour Services. Bureau of Special Services, Department of Tourism, 1992.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.