Answer: The Ugli fruit was found as a chance seedling in Jamaica. Since it appears to have mixed parentage, it may not grow true to type but instead bear more resemblence to its ancesters.
I have not been able to find any specific instructions on getting the seeds to germinate. However, you may get the help you need from the following site; this is a group of amateur fruit enthusiasts, and I bet someone there has had experience with ugli fruits.
California Rare Fruit Growers
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