http://www.suonoelettronico.com/synthesizer_vintage.asp?marca=SIEL&modello=CRUISE
http://m.matrixsynth.com/2011/05/siel-cruise-rare-fully-polyphonic.html
http://www.polynominal.com/site/studio/gear/sold/siel_cruisemono/index.html
http://www.synthark.org/Siel/Cruise.html