Joshua 4:20

"And those twelve stones, which they took out of Jordan, did Joshua pitch in Gilgal."

Cross References (ranked by relevance)

And command ye them, saying, Take you hence out of the midst of Jordan, out of the place where the priests’ feet stood firm, twelve stones, and ye shall carry them over with you, and leave them in the lodging place, where ye shall lodge this night.

Joshua 4:8

And the children of Israel did so as Joshua commanded, and took up twelve stones out of the midst of Jordan, as the LORD spake unto Joshua, according to the number of the tribes of the children of Israel, and carried them over with them unto the place where they lodged, and laid them down there.