aggiornamento:
Italian team, lead by professor Paolo de Bertolis of the University of Trieste, has performed another ultrasound recording on the top of the Bosnian Pyramid of the Sun in Visoko.
For the first time, one research group was given an opportunity to record the sound coming from the pyramid. It was performed in March 2012. Ultrasound has been converted to frequency of 8 kHz which can be recognize by our ears.
www.piramidasunca.ba/media/k2...ssage_2012.mp3