Chen, Qianxu, and Xin Yang. “A Study of Damage Mode Recognition of Polypropylene Fiber-Reinforced Recycled Aggregate Concrete Based on Principal Components of Acoustic Emission Signals”. Archives of Acoustics (June 24, 2026): 283–292. Accessed August 16, 2026. https://acoustics.ippt.pan.pl/index.php/aa/article/view/4407.