Hi visari_fizio
this is a huge topic so you will really need to think about focusing on something.
Katherine Sluka's book is a good text:
International Association for the Study of Pain | Mechanisms and Management of Pain for the Physical Therapist
And this article by her and Anthony Wright is a bit out of date but it is well put together:
Nonpharmacological Treatments for Musculoskeletal Pain : The Clinical Journal of Pain
The British CSP has a special interest group that has some good resources:
The Physiotherapy Pain Association Online
And Lorimer Moseley's site is well worth a look - very up-to-date and thinks outside the box:
Body in Mind ? Research into the role of the brain and mind in chronic pain disorders
All the best with your lecture