I could not feel more satisfied and at rest if the entire Whitmer family had testified

Mark Twain
Roughing It, Chapter 16

Witnesses of the Gold Plates and their relationship to Joseph Smith

Signatures (all in the handwriting of Oliver Cowdery)

Oliver Cowdery Co-founder, Cousin

David Whitmer Close Friend

Martin Harris Financial Backer

Christian Whitmer Close Friend

Jacob Whitmer Close Friend

Peter Whitmer, Jr. Close Friend

John Whitmer Close Friend

Hiram Page Friend, Related to Whitmers

Joseph Smith, Sr. Father

Hyrum Smith Older Brother

Samuel Harrison Smith Younger Brother

See https://www.churchofjesuschrist.org/study/scriptures/bofm/three?lang=eng & https://www.churchofjesuschrist.org/study/scriptures/bofm/eight?lang=eng