Dons at Oxford University are being urged to be vigilant against plagiarism among students.
Dons fear plagiarism could affect the value of an Oxford degree
The university's senior proctor, Professor Alan Grafen, said extensive copying of work would undermine the value of an Oxford degree.
Professor Grafen said all students should have to sign an affidavit for every piece of work they submitted.
But he denied newspaper reports that plagiarism among students at Oxford University was widespread.
Writing in Oxford Magazine, an in-house publication, Professor Grafen blamed schools for creating a culture of work "cobbled together from the internet".
He said students were arriving at university having had the practice of plagiarism endorsed.
He called for all new students at the university to have to attend a lecture on plagiarism, outlining exactly what was not acceptable.
The Telegraph newspaper claimed internet plagiarism at the university was "rife".
But Professor Grafen told the BBC news website: "I would not, and did not, say that plagiarism is 'rife' at Oxford."
He said the university had dealt with just 10 cases out of a total of 17,660 students.
"I would be surprised if Oxford was not near the bottom of national and world rankings for the incidence of plagiarism.
"It is a measure of the care we take with teaching and examining that my article was a response to such a small number of cases."
The issue of plagiarism among pupils as well as students has long raised concerns among educationalists.
Earlier last year, a report by the higher education technology organisation, Jisc, warned that student plagiarism was likely to become more common.
The report, Deterring, Detecting and Dealing with Student Plagiarism, suggested plagiarism was associated with higher levels of stress among students.
The need to take on paid work, heavier coursework load or lack of personal organisation skills may all be factors, the report said.
And a report by the Qualifications and Curriculum Authority (QCA) published in November found GCSE pupils had been copying each others' work and downloading essays from the internet.
It warned that copying essays from the internet could not be controlled. Now the Education Secretary, Ruth Kelly, has called for an urgent review of the use of coursework in GCSE subjects.