1. Random Number Service.
https://www.random.org
2. Pseudo-Random Number Generators.
https://crypto.stanford.edu/pbc/notes/crypto/prng.html
3. Lacharme, P., Röck, A., Strubel, V., Videau, M.: The Linux Pseudorandom Number Generator Revisited. Cryptology ePrint Archive, 251 (2012)
4. Dörre, F., Klebanov, V.: Practical detection of entropy loss in pseudo-random number generators. In: CCS 2016, Vienna, Austria, pp. 1–12 (2016)
5. Atanasova, T., Barova, M.: Exploratory analysis of Time Series for hypothesizes feature values. In: International Scientific Conference UniTech 2017, vol. II, pp. 399–403. University Publishing House V, Aprilov, Gabrovo (2017)