Based on standard medical reference databases and the known structure of Williams Gynecology (the companion to Williams Obstetrics ), here is the most likely interpretation of what you are asking for: You are referring to Chapter 30 of the 23rd Edition of Williams Gynecology (Spanish edition), which covers a specific clinical topic.
It seems you are looking for a specific (or distinctive characteristic) of the resource described as: "Gineco Obstetricia de Williams 23 edicion pdf 30" gineco obstetricia de williams 23 edicion pdf 30
If you need a specific from that chapter, let me know, and I can describe its content in detail. Based on standard medical reference databases and the