I just came across
https://www.ultracad.com/article_outline.htm series of articles, which is a good source. You're probably going to want to read
https://www.ultracad.com/articles/planesplits.pdf at least.
As the other posters said, keep analog and digital sections separate. I've never gone so far as to use a ferrite on the GND plane, just power, but instead just split the gnd planes and have them join at ONE point, an isthmus, as close as possible to where power enters the analog section/room. This is so the return current doesn't make a big loop (possibly through the digital side.) Either thru a jumper, or just use one GND plane but then use a line to almost cut it in two, with the join directly underneath the power ferrite+cap filter.
The GND split should go directly underneath any mixed signal ICs, like ADCs. So that the analog pins are on the analog side of GND and vice-versa. Make sure to read the datasheet about which GND pins are analog GND and which are digital GND. Make sure bypass caps are tied to the correct GND, too.
the GND split and power plane splits should line up. if they are staggered, you will get capacitance between analog GND and digital power, or digital GNDto analog power.
....ok, just got done typing that, then looked at dmd4raj's pdf files and lots of it is in there, better than I can describe it.