APA: 
Khan, Sajid Ali, Qasim, Hafiz Syed Ahmed, Azam, Irfan (2018). Feature extraction trends for intelligent facial expression recognition. 
Informatica (Ljubljana), letnik 42, številka 4, str. 507-514. 
URN:NBN:SI:DOC-CCB4OYRM from http://www.dlib.si
MLA: 
Khan, Sajid Ali, Qasim, Hafiz Syed Ahmed, Azam, Irfan. "Feature extraction trends for intelligent facial expression recognition." 
Informatica (Ljubljana) letnik 42. številka 4 (2018) str. 507-514.
<http://www.dlib.si/?URN=URN:NBN:SI:DOC-CCB4OYRM>