Reference 4111

(1942) Data and Circuits of Receiver and Amplifier Valves (1st supplement), Eindhoven: Philips.
View of the Philips Laboratories for Scientific Research at Eindhoven.
This publication was written in 1940 and 1941 when The Netherlands was occupied and gives an insight to the developments of the early 1940s.
For the PDF file click here.
Thanks to Stef Niewiadomski for finding this booklet and to Frank Philipse for having the PDF file.