{'https://www.mtu.edu/ece/department/faculty/full-time/zekavat/pdfs/ssp2015-jaffe3.pdf', 'https://www.ursi.org/files/RSBissues/RSB_334_2010_09.pdf', 'https://thedailydialectics.com/BOOTSTRAP/PICS/SurfaceWaves/INTLUnionofRadioScience.html', 'https://thedailydialectics.com/BOOTSTRAP/PICS/Space/SandwichConversionModulesforSpaceSolarPower.html'}