Valkenburgh, V. et al.(1966).The New Model Programmed Course of Elementary Technician Training Basic Industrial Electricity Part One (Part One).New York. USA:British and Commonwealth Edition First.
Gaya MLA
Valkenburgh, V. et al..The New Model Programmed Course of Elementary Technician Training Basic Industrial Electricity Part One.Part OneNew York. USA:British and Commonwealth Edition First,1966.Text.