Ancestry.com. A history and lineage of descendents of a Scottish family by the name of Sinclair [database on-line]. Provo, UT: Ancestry.com Operations Inc, 2004.Original data: Daub, St. Claire Lappe,. A history and lineage of descendents of a Scottish family by the name of Sinclair, who migrated from Scotland to Ireland in the seventeenth century : they settled in Newtownards, Co. Down and Belfast : according to family tradition, the Earl of Caithness was the head of the family : there are descendents in Ireland and England, in the middle nineteenth century, many emigrated to New Zealand, Australia, Nova Scotia and the United States of America. Springfield, Pa.: unknown, 1963.