APA (7 वां संस्करण) प्रशस्ति पत्र

Tourist Research & Planning T.R.P.Ltd Zug Switzerland. (1978). Manila portfolio. Tourist Research & planning T.R.P.Ltd Zug.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Tourist Research & Planning T.R.P.Ltd Zug Switzerland. Manila Portfolio. [Switzerland]: Tourist Research & planning T.R.P.Ltd Zug, 1978.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Tourist Research & Planning T.R.P.Ltd Zug Switzerland. Manila Portfolio. Tourist Research & planning T.R.P.Ltd Zug, 1978.