The crossing number of the circular graph C(2m+2,m)

The circular graph C(n,m) is such a graph that whose vertex set is {v0,v1,v2,…,vn-1} and edge set is {vivi+1,vivi+m|i=0,1,…,n-1}, where m,n are natural numbers, addition is modulo n, and 2⩽m⩽⌊n/2⌋. This paper shows the crossing number of the circular graph C(2m+2,m)(m⩾3) is m+1.