DJVU PDF Headley, R.K.Jr. 1998, "Cham evidence for Khmer sound changes", in Papers in Southeast Asian Linguistics No. 15: Further Chamic Studies, ed. D. Thomas, vol. 15, pp. 21-29. Pacific Linguistics, the Australian National University. cite.

DJVU PDF Headley, R.K. 1991, "The phonology of Kompong Thom Cham", in Austroasiatic Languages, Essays in honour of H. L. Shorto, ed. J.H.C.S. Davidson, pp. 105-122. School of Oriental and African Studies, University of London. cite.

DJVU PDF Headley, R.K.Jr. 1985, "Proto-Pearic and the classification of Pearic", in Southeast Asian Linguistic Studies Presented to André-G. Haudricourt, ed. S. Ratanakul et al., pp. 428-478. Institute of Language and Culture for Rural Development, Mahidol University. cite.

DJVU PDF Headley, R.K. 1978, "An English-Pearic vocabulary", in The Mon-Khmer Studies Journal, vol. 7, pp. 61-94. cite.

DJVU PDF Headley, R.K. 1977, "A Pearic vocabulary", in The Mon-Khmer Studies Journal, vol. 6, pp. 69-149. cite.

DJVU PDF Headley, R.K.,Jr. 1976, "Some Considerations on the Classification of Khmer", in Austroasiatic Studies, ed. P.N. Jenner et al., Honolulu, pp. 431-452. The University Press of Hawaii. cite.

DJVU PDF Headley, R.K.,Jr. 1976, "Some Sources of Chamic Vocabulary", in Austroasiatic Studies, ed. P.N. Jenner et al., Honolulu, pp. 453-476. The University Press of Hawaii. cite.