Chih-Duo Hong Yen-Pang Chen Fang Yu Signature filtering: A lightweight enhancement for statistical watermark detection in large language models. 2027 104998 64 Inf. Process. Manag. 1 https://doi.org/10.1016/j.ipm.2026.104998 db/journals/ipm/ipm64.html#HongCY27 streams/journals/ipm