Bovis-numbers accoring to German dowser Markus Schirner<ref>Schirner M, Pendel-Set, Schirner-Verlag, ISBN:3-930944-65-0</ref> | Bovis-numbers accoring to German dowser Markus Schirner<ref>Schirner M, Pendel-Set, Schirner-Verlag, ISBN:3-930944-65-0</ref> |