Deep Tissue Massage vs. Therapeutic Massage: Which One Is Right for You?

Sources & Further Reading

1. National Center for Complementary and Integrative Health (NCCIH)
This is our strongest general source. It explains massage therapy, its potential benefits for several pain conditions, safety considerations, and importantly notes that research hasn't established that one massage type is universally more effective than another.
Massage Therapy: What You Need to Know

2. NCCIH — Massage Therapy for Health: What the Science Says
A more research-focused resource covering massage for low-back pain, neck and shoulder pain, osteoarthritis, fibromyalgia and other conditions. This supports the therapeutic side of your comparison.
Massage Therapy for Health: What the Science Says

3. NCCIH — Chronic Pain and Complementary Health Approaches
Useful because your article discusses choosing massage according to what the person is actually experiencing rather than simply choosing the deepest massage available. NCCIH summarizes evidence for massage as one of several approaches that may help manage certain painful conditions.
Chronic Pain and Complementary Health Approaches

4. NCCIH — Massage Therapy Safety
This one is particularly relevant to deep tissue massage. NCCIH notes that massage generally has a good safety record but that rare serious adverse effects have been reported, some involving vigorous massage such as deep tissue. It also notes circumstances in which forceful/deep massage may be inappropriate.
Massage Therapy: Safety and Considerations