resources/metadata/372/altformats.csv - external/libphonenumber - Git at Google

 Format         ; Parent Format ; Comment
 6 XXX XXX      ; all_3/4       ; "There are about 2 million search results for numbers written with the 6 separate."
 [4-79]X XX XXX ; all_3/4       ; "Some prefixes have been seen in this format too."
 [4-79]X XXX XX ; all_3/4
	Format ; Parent Format ; Comment
	6 XXX XXX ; all_3/4 ; "There are about 2 million search results for numbers written with the 6 separate."
	[4-79]X XX XXX ; all_3/4 ; "Some prefixes have been seen in this format too."
	[4-79]X XXX XX ; all_3/4