Wenbo, L. (2013). Opa application development: A rapid and secure web development framework to develop web applications quickly and easily in Opa. Packt Pub..
Čikaški stil citiranja (17. izdanje)Wenbo, Li. Opa Application Development: A Rapid and Secure Web Development Framework to Develop Web Applications Quickly and Easily in Opa. Birmingham: Packt Pub., 2013.
MLA način citiranja (9. izdanje)Wenbo, Li. Opa Application Development: A Rapid and Secure Web Development Framework to Develop Web Applications Quickly and Easily in Opa. Packt Pub., 2013.
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