“IMPEDANCE MODELLING OF METAMATERIAL STRUCTURE BASED ON DOUBLE QUAD-SQUARE SPLIT RING RESONATOR (DQS-SRR) AT 2.4 GHZ AND 7.4 GHZ”, J. Teknol., vol. 78, no. 5-7, Jul. 2016, doi: 10.11113/jt.v78.8727.