Full file date (without GNU utilities)

I am trying to obtain the full date (created or modified) of a particular file for passing to another program. I have tried variations of options with the ls command but none provide a full date for files less than 6 months old and I have limit usage of the options. When I try certain options I have seen trying to research this I get the following message: usage: ls [-1ACFHLNRabcdefgilmnopqrstuxEUX] [File...] None of which seems to provide what I needs as far as I can tell so I tried to use the stat command but it is not available to me. I am using the Korn shell on AIX 5.3 which has limited commands available, can anyone suggest another way that I might be able to obtain a file's created or modified date as a full date (either dd/mm/yyyy or yyyy/mm/dd).