pub by George Allen & Unwin Ltd.

Astro-Navigation Part 1.Card cover,4th imp 1941, vg, no d/w. £3

Astro-Navigation Part 2.Hard back, int nr fine but cover & d/w only g.3nd imp. £4.50

Astro-Navigation Part 2 Card cover,vg, damaged d/w. £4

Dead Reckoning Navigation.Hard back ;nr fine inc d/w.1st 1940. £6

Another copy, Card cover.vg inc d/w.6th imp 1941. £5

Radio Navigation. Hardback, vg+,vg d/w 1st 1941. £6