Looking for defensive tactics' resources....

Calling out to all bloggers out there...

Most of the resources (chess.com tactics trainer/ chess tempo/ Polgar puzzles/ any other tactics book) that we have for Tactics training are geared towards attack on the opponent. Among the tactics trainers/ puzzles from above sources, they cover defensive aspect of the tactics only about 10 - 15% at best, I feel. Rest of it 85% is geared towards attacking the opponent's pieces. There are very few books like Solits' "Art of Defense" available but these are also not so good.  

As a result, most budding players often know how to attack but are poor defenders. Most of my students have varying strength in defense vs attack. If they are rated 1200 in attacking tactics, they would be at 800 rating on defensive tactics.

I would like to know from you all any resources that concentrate on defensive side of tactics. I am looking for a complete tactics book with many puzzles/ exercises which covers Defensive tactics better like ~ 50% defensive tactics and 50% attacking tactics. Or please suggest me a website if possible.

Thanks...