[zerozio2u]

Rule <R5> d. "Teams may add non-functional decorations from parts not on the above list, provided that these parts do not affect the outcome of the match, and must be in the spirit of 'Gracious Professionalism'."
The label is and non-functional "decorations" and it will "not affect the outcome of the match." I personally think that paper and tape are considered to be decorations. By logic, paper and tape could be use as labels.