Dostupné online Old Faithful: Geological Wonder "Old Faithful" "Old Faithful" Old Faithful Informationen der Geyser Observation and Study Association Old Faithful "Old Faithful" Old Faithful Old Faithful, The Geyser Observation and Study Association оригіналу оригіналу www.geyserstudy.org Old Faithful "Old Faithful" http://www.geyserstudy.org/geyser.aspx?pGeyserNo=OLDFAITHFUL