A compact ultra-wideband bandstop filter using mu-negative and ENZ metamaterial resonators for multiple advanced wireless communication systems - Mouhssine Elbathaoui; Nawfal Jebbor; Sudipta Das; Wael Ali; Sahaya Anselin Nisha Arockiam; Om Prakash Kumar; El-Mahjoub Boufounas (PLoS ONE, 2025)