Jelaskan Jenis-jenis cegah pengintipan dari Perisikan balas dalam bahasa melayu

Johnson, William R. Thwarting Enemies at Home and Abroad: How to Be a Counterintelligence Officer'' (2009)

Bibi van Ginkel,Towards the intelligent use of intelligence: Quis Custodiet ipsos Custodes? (International Centre for Counter-Terrorism - The Hague, 2014)