Oliver Cowdery, David Whitmer, and Martin Harris are shown the plates by an angel . David Whitmer said the event occurred in the "latter part" of June 1829 . Whitmer told Edward Stevenson that the vision occurred on a "Sunday" about 11:00 a.m., perhaps 28 June . Whitmer also said he was shown the plates "shortly before the completion of the translation when but a few pages left".
[Vogel, Dan, Early Mormon Documents, Appendix B: Chronology, 1771-1831, http://amzn.to/T5nY8w]