Severity: Notice
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Filename: controllers/presentation.php
Line Number: 875
Severity: Notice
Message: Trying to get property of non-object
Filename: controllers/presentation.php
Line Number: 875
Author(s):
1. Svjetlana Janjić, Faculty of Technology Banja Luka,
Republic of Srpska, Bosnia and Herzegovina
2. Jovana Milanović, Tehnološko-metalurški fakultet, Univerzitet u Beogradu, Srbija, Serbia