Community Tip - You can change your system assigned username to something more personal in your community settings. X
pdf looks like there is a significant effort here! But there's no sheet.
Are you advertising for sale?
Hi!
I publish for any of the reasons you mentioned. I do it for generosity to the Youths newbies interested in the subject, and I hope to do it right ... then if there will be unexpected developments, they are welcome. But I do not think there will be, the subject being very old, namely of the last century.
Bye