@ARTICLE{Kushnir_O._Simple_2015, author={Kushnir, O.}, number={No 4}, journal={ECONTECHMOD}, howpublished={online}, year={2015}, publisher={Polish Academy of Sciences Branch in Lublin}, publisher={Lviv Polytechnic National University}, publisher={Foundry Research Institute in Cracow}, title={Simple expressions for the designing of the double bandpass optical filter}, }