Link to original site

I am using wordpress 2.5 on my site https://www.emanualmedicine.com that diplay news from various sources.
Im using permalink to point to my site https://www.emanualmedicine.com/articles/index.php/massage-therapy/the-trigger-point-therapy-workbook-your-self-treatment-guide-for-pain-relief-second-edition-paperback-tagged-massage-21-times/ but also in the post page I would like to include a link to original site as if I was using the using the permalink option pointing to the original site, that is https://www.amazon.com/Trigger-Point-Therapy-Workbook-Self-Treatment/dp/1572243759/ref=tag_rso_rs_edpp_url?ie=UTF8&tag=emanual-20&creative=381421.

I foun something similar but they link to original site but not to original page
<p>Written by:
<?php the_author_link(); ?></p>
<p>Original Article:
<?php the_author_url(); ?></p>

Furthermore there is a problems with the url lenght.

As you can see on this page https://www.emanualmedicine.com/articles/index.php/category/products/
the link to Original Article is incomplete: https://www.amazon.com/tag/massage/products/ref=tag_rso_rs_istp_chanlink?sort=relevant&tag=emanua
https://www.amazon.com/tag/myofascial%20pain/products/ref=tag_rsn_rs_istp_chanlink?sort=recent&ta
https://www.amazon.com/tag/rehabilitation/products/ref=tag_rso_rs_istp_chanlink?sort=relevant&tag

Any help is very much appreciated

Regards