where do i place a comma

[Unregistered]

In the following sentence:

In this article by Lawrence Kohlberg a well-known theorist to modern psychology, wrote about the cognitive-developmental-approach to moral education.

 

[Horsa]

Both sides of the non-defining relative clause. I made 2 other small changes.

In this article Lawrence Kohlberg, a well-known theorist in modern psychology, wrote about the cognitive-developmental-approach to moral education.