“Experimental and Numerical Assessment of Low-Frequency Current Distributions from UMTS and GSM Mobile Phones,” Physics in Medicine and Biology, December 7, 2013, from Niels Kuster's group in Zurich.
“The LF fields [<20 kHz] generated by mobile phone battery currents are, thus, not compliant with the ICNIRP reference levels for normal use, i.e., at the head.”