Tyler Hamilton's appearance on 60 Minutes alleges among other things, Lance Armstrong's doping, encouragement of doping on his teams, and covering up of a positive doping test. 

In response, Lance Armstrong has called into question Tyler Hamilton's credibility.  In a statement, Armstrong's representatives say clearly that Hamilton is not credible person. 

The statement, published through a website supporting the seven time Tour de France winner, alleges that throughout Hamilton's career, he has had a history of doping denials, despite admitting to doping on the 60 Minutes interview.

Other things alleged in the statement about Tyler Hamilton's cycling career include:

Quote: Tyler Hamilton in the past has testified that he did not dope.  Now, he has changed his story - perhaps because he wants to make money from writing a book.

Quote: At least two journalists fact-checked Hamilton's college-degree claim and declared it to be untrue.  Hamilton was enrolled at Boulder for three years, majoring in economics, but never received a degree.

Quotes Christie Aschwanden, a person who knew Hamilton in college say that Hamilton's college degree lie wasn't a small lie either.  Aschwanden continues, It was one that, in many instances, has ruined careers and ended in resignations.

Quotes David Walsh, an author say that Tyler Hamilton has an occasionally cavalier attitude toward the truth

Quotes Hamilton as telling USADA lawyers it was a massage of the truth in reference to saying a 2004 bladder infection was a stomach infection.