Practical and mental arithmetic: on a new plan: in which mental arithmetic is combined with the use of the state, containing a complete system for all practical purposes ... Cavy and Burgess, 1850 - 282 σελίδες |
Practical and mental arithmetic: on a new plan: in which mental arithmetic is combined with the use of the state, containing a complete system for all practical purposes ...Cavy and Burgess, 1850 - 282 σελίδες |