Items in Old Church Slavic often follow the old manuscript practices and abbreviate words by omitting letters followed by the mark of omission.

• In the 245 field, insert the missing letters without using brackets.
• Make an added title reference for the actual form of the title.

Example:

If the missing letters cannot be determined, substitute a question mark within the brackets ([?]). LCRI 1.0E

• The ALA-LC Romanization Tables (1991) states that brackets are not used (p. 41)