Atac, Robert; Spink, Scott; Calloway, Tom; Foxlin, Eric (2014-06-13). "Scorpion Hybrid Optical-based Inertial Tracker (HObIT) test results". In Desjardins, Daniel D; Sarma, Kalluri R; Marasco, Peter L; Havig, Paul R; Browne, Michael P; Melzer, James E (eds.). Proc. SPIE 9086, Display Technologies and Applications for Defense, Security, and Avionics VIII; and Head- and Helmet-Mounted Displays XIX. Vol. 9086. pp. 172–181. doi:10.1117/12.2050363. S2CID121689580.
Atac, Robert (2010-05-05). "Applications of the Scorpion color helmet-mounted cueing system". In Marasco, Peter L; Havig, Paul R (eds.). Proc. SPIE 7688, Head- and Helmet-Mounted Displays XV: Design and Applications. Vol. 7688. pp. 18–24. doi:10.1117/12.849287. S2CID120094908.
Atac, Robert; Spink, Scott; Calloway, Tom; Foxlin, Eric (2014-06-13). "Scorpion Hybrid Optical-based Inertial Tracker (HObIT) test results". In Desjardins, Daniel D; Sarma, Kalluri R; Marasco, Peter L; Havig, Paul R; Browne, Michael P; Melzer, James E (eds.). Proc. SPIE 9086, Display Technologies and Applications for Defense, Security, and Avionics VIII; and Head- and Helmet-Mounted Displays XIX. Vol. 9086. pp. 172–181. doi:10.1117/12.2050363. S2CID121689580.
Atac, Robert (2010-05-05). "Applications of the Scorpion color helmet-mounted cueing system". In Marasco, Peter L; Havig, Paul R (eds.). Proc. SPIE 7688, Head- and Helmet-Mounted Displays XV: Design and Applications. Vol. 7688. pp. 18–24. doi:10.1117/12.849287. S2CID120094908.