Fascinating African National Congress manual for covert actions, which was published during 1988-90. Check this out:
Secret methods are based on common sense and experience. But theymust be mastered like an art. Discipline, vigilance and self-control are required. A resistance organiser in Nazi-occupiedFrance who was never captured said this was because he `neverused the telephone and never went to public places like bars, restaurants and post offices. He was living a totallyunderground life. But even those members of a secret movement who have a legal existence must display the qualities we have referred to.
http://cryptome.org/anc-manual.htm
