That is, the location of Wang Wen's hexagrams:
Kanbei, Nanlin, Zhendong, Duixi, Northwest Gansu, Southeast Xunxun, Southwest Kunming and Northeast Gengen.
In geomantic omen, we always use the acquired gossip to determine the actual geographical location. Innate gossip, on the other hand, does not need to determine the actual location, but is used to judge the expiration time.
It can also be said that gossip is a spatial model and innate gossip is a time model. The interaction of the two forms a geomantic system.
As for the source of the quotation, there are too many. Famous Feng Shui books have very detailed explanations. For example, Shen Shi's metaphysics, house method, geomantic omen and so on. There are so many books on Feng Shui that you can take them with you in the car, so I won't give them one by one.