By practicing some basic communication patterns, a person in almost any business can learn how to enable others to be prolific sources or advocates. It's up to him to coach sources so they have the conviction and the communication to get others to call for an appointment. A person requesting referrals needs to realize that referral sources are concerned with their own needs, priorities and constraints. By seeing referrals from the source's perspective, business people wanting referrals will phrase a request for qualified prospects in such a way that makes it easy for others to become their advocates. Remember that generating referrals is a subconscious effort.
Sources have their own lives to lead.
When they grasp value on the subconscious level and see someone with money in motion, they begin sharing that person's benefits spontaneously. They become the person's advocate. Make it simple for the source to provide the reference. Sources may not know what to say if they have not been prepared by the person wanting the reference. They may think they have to talk about money, when in reality they will promote the service.