I've been in this country 30+ years with an indefinite green card but never really bothered to fill out the papers -- I know, I know, let's not go there now.  One question on the N-400 form asks about all my travels since I was admitted to the country.  I have gone through a few passports since then and they were not stamped every time so consequently I have spotty documentation of all travels but the most recent.  Would a supplement explaining this suffice?  I am really interested to know as I am ready to file the papers.  Thanks!