Where can I find the real proof that this is true? I'm a young (very young) agent who is having hard time getting seniors to trust my statements, and need legal proof for just about everything i say.
While I understand it's nice to have something in hand to get to Seniors for reassurance, as you start out in your new career I'd highly suggest you don't make a habit of this and work much harder on a rock-solid presentation and showing them you are the authority in the conversation. If you can't do this over time you'll be retrieving and handing out a lot of information and working for free.
Your "hard time getting Seniors to trust your statements" isn't a lack pdf's you can email them, it's a lack of a skill that you'll need to work on. Great news is you're young. Studies have shown putting in 10,000 hours of hard work and training into your profession can put you in the top 5% in your field. Go for it.