1. Anon.: The compendium report: The US JHSAT baseline of helicopter accident analysis, Volume II, (CY2000, CY2001, CY2006). In: US Joint Helicopter Safety Analysis Team (2011)
2. Anon.: EHEST Analysis of 2006–2010 European helicopter accidents. European Helicopter Safety Team (2015)
3. Van Donghen, N.: Final report of NIAG SG167 on helicopter operations at low altitude degraded visual environment (DVE). NIAG-D(2013)0014, AC/225(VL)D(2013)0001 (2013)
4. Münsterer, T., Scheuch, J., Völschow, P., Strobel, M., Roth, M., Fadljevic, D.: Capability Comparison of Pilot Assistance Systems Based Solely on Terrain Databases Versus Sensor DB Fused Data Systems. In: Proc. SPIE 9839, Degraded Visual Environments: Enhanced, Synthetic, and External Vision Solutions 2016, 983905 (2016)
5. Air Accident Investigation Unit Ireland: Preliminary Report, Accident Sikorsky S-92A, EI-ICR, Black Rock, Co. Mayo, Ireland (2017)