Look up "circa" in a style manual, such as the Chicago Manual of Style, and use it consistently; both c. 1890 and ca. 1890 are correct. However, c1890 means "copyright 1890" to librarians, not "circa." David Haberstich ========================================================= Important Subscriber Information: The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes). If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).