## Proof of Lemma 6.3 in The crossing number of $K_{4,n}$ on the torus and the Klein bottle"

Ho, Pak Tung
##### Description
We found that Lemma 6.3 in the paper The crossing number of $K_{4,n}$ on the torus and the Klein bottle" is wrong.
##### Keywords
Mathematics - Combinatorics, 53C10