Position Location Based on RSSI

What algorithms is used for "Position Location Based on RSSI" for short range (Max 1000m) rf modules?

Is there any link for pdf?

I suspect that this is done by reveres LORAN. Instead of having three transmitters, there are three receivers. Taken in pairs and comparing the time of arrival or signal strength you get a hyperbola of all possible locations. From the two curves you get the intersection which is the emitter location.

is there any detail infor in a pdf or book or article?

I only know of two LORAN books. One is in the MIT RADLAB series and the other is Terman's 1955 fourth edition of his famous handbook. You can find these used on bookfinder.com