Tourist Research & Planning T.R.P.Ltd Zug Switzerland. (1978). Manila portfolio. Tourist Research & planning T.R.P.Ltd Zug.
Chicago-viite (17. p.)Tourist Research & Planning T.R.P.Ltd Zug Switzerland. Manila Portfolio. [Switzerland]: Tourist Research & planning T.R.P.Ltd Zug, 1978.
MLA-viite (9. p.)Tourist Research & Planning T.R.P.Ltd Zug Switzerland. Manila Portfolio. Tourist Research & planning T.R.P.Ltd Zug, 1978.
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