1. Programming pearls
2. Christiansen T. 1995. Csh programming considered harmful. Internet FAQ Archives; http://www.faqs.org/faqs/unix-faq/shell/csh-whynot/. Christiansen T. 1995. Csh programming considered harmful. Internet FAQ Archives; http://www.faqs.org/faqs/unix-faq/shell/csh-whynot/.
3. DiBona , C. , Ockman , S. , Stone , M. , editors. 1999 . Open Sources: Voices from the Open Source Revolution . O'Reilly Media . DiBona, C., Ockman, S., Stone, M., editors. 1999. Open Sources: Voices from the Open Source Revolution. O'Reilly Media.
4. GNU grep. 2022; https://www.gnu.org/software/grep/. GNU grep. 2022; https://www.gnu.org/software/grep/.
5. Hanson D. R. 1997. C Interfaces and Implementations. Addison-Wesley. Hanson D. R. 1997. C Interfaces and Implementations. Addison-Wesley.