[fatghost13]

Can any one provide some reference for me to have a look

[Arkcon]

You're asking for a common fact, about a molecule that's been known for at least a century.  In a situation like that, you should try Wikipedia first:  http://en.wikipedia.org/wiki/Ozone#Structure  I'm sorry that section doesn't have a particular reference cited.  But, you should check to references at the bottom of the page.  Or maybe the references given in a textbook, if they do that.  Or a quick literature search for ozone, pick any recent article,  then check it's intro for references, to see if you can get an early discussion on the topic.

[EDIT]

For example, start here:  http://jcp.aip.org/resource/1/jcpsa6/v66/i12/p5278_s1?isAuthorized=no  if you can get access to that article, it may start with references to the structure of ozone