Possible Clues:

• Q&A on Reddit
• Org. with an influential journal
• Docs' org. with a noted journal
• "I ___ Rock" (Simon & Garfunkel song)
• Dr.'s gp
• Simon & Garfunkel's "I ___ Rock"
• Doc's gp
• G.P.'s gp
• Org. with a much-quoted journal
• Sawbones' gp