onComplete, onStart, and onTween share similar typos in the API documentation at http://developer.yahoo.com/yui/docs/YAHOO.util.Anim.html

E.g., for onComplete,

[quote]
Custom event that fires when animation ends Listen via subscribe method (e.g. myAnim.onComplete.subscribe(someFunction)
[/quote]

Two typos in each event--a missing period and a missing ')'.

[correct]
Custom event that fires when animation ends. Listen via subscribe method (e.g. myAnim.onComplete.subscribe(someFunction))
[/correct]

or alternatively:

Custom event that fires when animation ends. Listen via subscribe method; e.g., myAnim.onComplete.subscribe(someFunction)