How about AN1831?
I have attached a file that provides a simple sub-routine that erases the first page (64 bytes) of flash memory, and programs the data into the first 32 byte block. This should be satisfactory provided the stored data doesn't have to be re-written too often. If more frequent re-writes are required, the more complex method of AN2346 might be used.
For the simple case, no special measures are required to read the programmed flash bytes.
Retrieving data ...