Coggeshall, J., & Tabini, M. (2005). The Zend PHP certification practice test book: Practice questions for the zend certified engineer exam. Marco Tabini & Assoc..
Chicago-viite (17. p.)Coggeshall, John, ja Marco Tabini. The Zend PHP Certification Practice Test Book: Practice Questions for the Zend Certified Engineer Exam. Toronto, Ont.: Marco Tabini & Assoc., 2005.
MLA-viite (8. p.)Coggeshall, John, ja Marco Tabini. The Zend PHP Certification Practice Test Book: Practice Questions for the Zend Certified Engineer Exam. Marco Tabini & Assoc., 2005.
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