Yes Stan, thank you but I also followed that question by asking:
2. For indexing purposes if no preferred surname is stated on a bc how are current entries indexed? Father's name/ mother's maiden name/ a.n.other/both?So I guess you were answering Q1. .. thank you Stan

Thank's Toni for the link - at the bottom of the page there is a PDF regarding
Index information that looks like it contains the answers to my query. Ta.
Kind regards all
