1. Siemens PLC Simatic S7-300, Elektronski fakultet, Katedra za automatiku, Univerzitet u Nišu. Dostupno:
http://automatika.elfak.ni.ac.rs/82-icecation/100-plc-reklama.html
2. Application of PLC in mechatronics, Department of Energy Electronics and Converters, Faculty of Technical Sciences, Novi Sad.
http://www.keep.ftn.uns.ac.rs/predmeti/masinski_4g_PrimenaPLC_u_meh/Industrijs%20kaInformatika.pdf
. Accessed May 2018
3. SIMATIC HMI, WinCC SCADA, SIEMENS:
http://w3.siemenscom/mcms/automation/en/human-machine-interface/Pages/Default.aspx
. Accessed July 2018
4. Srivastava, M.D., Prerna, S.S., Sharma, S., Tyagi, U.: Smart traffic control system using PLC and SCADA. Int. J. Innov. Res. Sci., Eng. Technol. 1(2), 169–172 (2012)
5. History of Traffic Signs:
https://www.educentar.net/Vijest/10411/Povijest-prometnih-znakova
. Accessed Apr 2019