You can find links to the first three below:
Don't be afraid to challenge the pros, even in their own backyard.
I love the last line of this one... "Good leadership encourages everyone's evolution." Think about your team. If you have an expert on your team, congratulations. But is that expert continuing to grow? The rate of human knowledge growth is exponential. That means it continues to grow at an ever increasing rate. If you have 30 years in a field, are you aware of the changes in the last six months? Test your experts, and don't accept them at face value. They gained their knowledge from a lot of hard work, but if they are relying solely on that old knowledge, then you (and they) are hurting the team.
Scrubs, a pretty good sitcom, had an episode with Dick Van Dyke makes a guest appearance. Dick was a doctor with over 30 years experience, and continued to treat patients the "old, reliable way." In fact he even said during the show that he doesn't have the energy to keep up with the new medical discoveries. In the end, Bob Kelso (the head of the hospital), had to let his friend go because he was endangering people with his out-of-date treatments. Funny to find a leadership lesson in a sitcom, but there it is.
If you find yourself with an "expert" who isn't growing anymore, you need to challenge them. If they aren't challenged, they won't grow, and you may be putting your team in danger with out-of-date techniques. Scary thought, isn't it?