Dr.Freschi,
Thanks for your response. I would mention a link here ,which may be useful to you.

www.historymuseum.ca/cma/exhibitions/civil/maya/mmc05eng.shtml.( Ref-Canadian Museum of History)

I would also mention a line from the link,which goes as follows- 'That the Maya understood the value of
zero is remarkable -most of world's civilisations had no concept of zero at that time'

The moot point is that the Mayans may not be using zero as a place-value ,as efficiently as the
Bakshali mms did, but ,if the issue is that of ORIGIN OF ZERO ,then, would be out of place to grant the
Mayans this honour?

ALAKENDU DAS