1. See also: http://maritime-explorations.con/belitung.htm.
2. The first ideas of this paper were conceived sometime in November 1974, during a conversation with Prof. Jose Maceda, when we were notating, playing, and recording his composition, Atmospheres, thereafter renamed Ugnayan, a piece for twenty radio stations, broadcast in Manila on 31 December 1974. Prof. Maceda suggested that the study of a history of gongs in Asia can be related to the much better documented ceramic finds.
3. Wong, Grace 1979 A Comment on the Tributary Trade between China and Southeast Asia, and the Place of Porcelain in This Trade during the Song Dynasty in China. Transactions of the Southeast Asian Ceramic Society, 7. Singapore: The Southeast Asian Ceramic Society. (Also published in: Chinese Celadons and Other Related Wares in Southeast Asia (Singapore: Singapore Asian Ceramic Society, 1979): 73–102)
4. The Butuan Archaeological Finds: Profound Implications for Philippine and Southeast Asian Prehistory;Ronquillo;Man and Culture in Oceania,1987
5. Some Thoughts on the Pre-Ming Trade Potteries Found in the Philippines;Locsin;In “A Report on the Archaeology of the Locsin-University San Carlos Excavations in Pila, Laguna, September,1968