The vertical columns of inverted Vs reflect the exact shape of the two pairs of diagonally placed massive stones standing above the Mouth of the Great Pyramid of Khufu's at Giza. In the Giza pyramid, these stone blocks stand above the "Twin Breasts" at the Pyramid's main entrance. The Twin Breasts represent the Twin Hills between which the Sun God Atum-Ra rises on his daily journeys. The twin hills are called DN (DUN/DAN) in Egyptian and Sumerian, and they go back to the Twin Hills overlooking the Dunu Oka Shrine of Atum/Osiris in the Lejja Horizon/Shrine in Nigeria.
This inverted V-construction is called "SHISHE-HEWN" in Egyptian architecture. And it is the Sumerian letter SHI. When repeated as in the Bosnian examples, it spells SHI-SHI or SHI-SHE. Shishe is the Egyptian/Sumerian goddess of Architecture, Pyramid Building, and Writing. She was the wife/consort of Thoth who is the god of writing and the leader of the Khemennu scribes.