mc_rebalance_datapack/data/minecraft/recipes/book.json

{
	"type": "minecraft:crafting_shapeless",
	"category": "misc",
	"ingredients": [
		{"item": "minecraft:paper"},
		{"item": "minecraft:paper"},
		{"item": "minecraft:paper"},
		{"item": "minecraft:rabbit_hide"}
	],
	"result": {"item": "minecraft:book"}
}