I don't want to start a fight with
@Cycleops ...but... this is a very rare bike. As the links that
@classic33 and
@bagpuss show Special Corsa Monzas were made (well labeled as monzas) in 1961 only. My guestimate would be 150 of them maximum.
Does it fit you? if so I suggest you keep it, ride it, enjoy it and look after it.
If you are interested in the value, much will depend on the condition, but I've never seen a Cinelli from that era sell for under four figures.