A President and a certificate that could, in theory, disqualify him from office.
President Erdogan's official biography states that he graduated from Maramara University's Economic and Commercial Sciences Faculty in 1981.
But in recent days Turks have taken to Twitter under the hashtag #YaDiplomaYaİstifa - which means Either Your Diploma Or You Resign - accusing the president of lying. Tens of thousands of tweets have used the hashtag and there's even a music video which calls on the president to produce evidence of his higher education.
The President isn't helped in the matter by the official website of Marmara University, which states that the aforementioned faculty never existed, but that the Faculty of Economic and Administrative Sciences was formed in 1982.
Doubts about the authenticity of Erdogan's degree were first made by an opposition MP before his election as President in 2014, with claims that the archives of Marmara University was closed during the Presidential election of 2014. And in the past few days the conversation has resurfaced as a result of the re-sharing of old reports saying that the Marmara University archives have since been reopened, and the President's degree can not be found.
Erdogan's opponents have been particularly vocal as having a four-year degree is officially a prerequisite for becoming president - though it's not clear if he could be disbarred from office if his degree was ruled to not be genuine.
This tweet reads: "Don't bow down to a phony, my Turkey!"
Many of the other critical tweets focussed on the lack of an official response from President Erdogan to the accusations.
The tweet below has Erdogan saying "You don't have a diploma as well, right?" To which President Obama replies, "Dude I'm a Harvard graduate ;)"
Erdogan is the holder of a number of honorary degrees. And ironically was awarded one in Uganda this week on his tour of East Africa just as the controversy was raging at home. His supporters have defended him, saying he is more than capable of handling the naysayers.
Discussion of the President's eligibility has extended beyond social media. The former chairman of the Association of Judges and Prosecutors (YARSAV), Omer Faruk Eminagaoglu has appealed to the Supreme Election Board (YSK) of Turkey to annul Erdogan's presidency. He submitted a 29 page document in support of his appeal, claiming that a necessary review of his eligibility was not carried out prior to his election as President. He also called for the Ankara's Chief Public Prosecutor to begin an investigation into Erdogan's alleged "use of forged official documents".
President Erdogan has yet to respond to the allegations.
Blog by Tural Ahmedzade, BBC Monitoring
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