Commonwealth Bureau of Census and Statistics2025-09-192025-09-1912.16.52https://hdl.handle.net/1885/733781210application/pdfen-AUProduction Summary No.52, Electrical Power Frequencies, Transformers, Chokes, and Ballasts, August 19701970-08This image is provided for research purposes only and must not be reproduced without the prior permission Australian National University.