​Four Melbourne academics have been sacked for forcing students to buy unauthorised e-textbooks in order to pass compulsory tests.

RMIT University on Thursday said the School of Economics, Finance and Marketing academics had been dismissed following an independent audit by PricewaterhouseCoopers.

Students were told to buy $50 ebooks written by their lecturers as part of the scheme.

RMIT’s pro-vice-chancellor of business Professor Ian Palmer said the academics were sacked on Wednesday after they breached the university’s conflict of interest policy.

“In light of the external investigation, RMIT has taken disciplinary action against the four academics, and their employment ceased yesterday,” Palmer said on Thursday. “RMIT will offer to reimburse affected students for the costs incurred in purchasing e-books in order to access compulsory online quizzes.”

Prof Palmer said no students had been academically disadvantaged in the scheme.

The academics were stood down with full pay in September ​.

It is understood the academics were lecturers, and students in some business subjects had to complete the assessments via the ebook company website owned by one or more of the lecturers.

The books could not be resold, transferred to another student, or shared.

The National Union of Students in September described the lecturers’ conduct as a “breach of the trust between student and teacher”.