The following options are available when you select Bibliography as the index type.
Choose Insert - Table of Contents and Index - Table of Contents, Index or Bibliography - Type tab (when Bibliography is the selected type)
Type and Title
Specify the type and title of the index.
Select the type of index that you want to insert. The options available on this tab depend on the index type that you select. If the cursor is in an index when you choose the Insert - Table of Contents and Index - Table of Contents, Index or Bibliography, you can then edit that index.
Enter a title for the selected index.
Protected against manual changes
Prevents the contents of the index from being changed. Manual changes that you make to an index are lost when the index is refreshed. If you want the cursor to scroll through a protected area, choose Tools - Options' - LibreOffice Writer - Formatting Aids', and then select the Enable cursor check box in the Protected Areas section.
Formatting of the entries
Automatically numbers the bibliography entries. To set the sorting options for the numbering, click the Entries tab.
Select the brackets that you want to enclose bibliography entries.
Sets the options for sorting the index entries.
Select the language rules to use for sorting the index entries.
Select numeric when you want to sort numbers by value, such as in 1, 2, 12. Select alphanumeric, when you want to sort the numbers by character code, such as in 1, 12, 2.