1. Bauman & Haldi. (1992). Heart rate under control. User manual. Fleurier, Switzerland: Author.
2. Gogh, K.T. (1990). Sudden unexplained death Syndrome among Thai workers in Singapore. Paper presented at the National Epidemiology Seminar, Bangkok, Thailand.
3. Hasle, P., Chavalitnitikul, C. & Takala, J. (1985). Survey of working conditions and environment in small-scale enterprises in Thailand. In Proceedings. International Symposium on Ergonomics in Industrially Developing Countries, Jakarta (pp. 464–471). Geneva, Switzerland: International Labour Office.
4. Intaranont, K. & Vanwonterghem, K. (1993). Study of the exposure limits in constraining climatic conditions for strenuous tasks: An ergonomic approach. Unpublished manuscript, European Commission (DGXII RTD), Brussels, Belgium.
5. International Organization for Standardization (ISO). (1982). Hot environments–Estimation of the heat stress on man, based on the WBGT-Index (wet bulb globe temperature) (Standard No. ISO 7243). Geneva, Switzerland: Author.