Formatting issue with percentage sign

While inserting reference in the document where % sign is present occurs something odd. RM inserts reference number at the % sign.

For example:

“As it has been noted that bilateral CPFs frequently [**Levin 1978]**9 terminate into the pulmonary artery 10 compared to the unilateral CPFs which drain in the pulmonary artery.”

The original text was pulmonary artery (56%) and RM changed into pulmonary artery 10

While this reference number is not required in this area.

The used RM is version 12. Bld 2401