Bird, I. G., Wishart, E. R., & Illingworth, J. J. (1971). A photoelectric snow drift gauge. Printed by Defence Printing Establishment, Department of Supply.

Bird, I. G., E. R. Wishart, and J J. Illingworth. A Photoelectric Snow Drift Gauge. Brunswick, Vic.: Printed by Defence Printing Establishment, Department of Supply, 1971.

Bird, I. G., et al. A Photoelectric Snow Drift Gauge. Printed by Defence Printing Establishment, Department of Supply, 1971.