BBasis[7,{4, 4}] =
{Graph[C1[19], C1[18], C1[17], C1[16], C2[19], C2[18], C2[15], C2[14], 
   Dashed[17, 19], Dashed[16, 17], Dashed[14, 18], Dashed[15, 16], 
   Dashed[14, 15], OV[8, 11, 13], OV[7, 12, 13], OV[4, 10, 12], 
   OV[3, 9, 10], OV[2, 6, 11], OV[1, 5, 9]], 
  Graph[C1[18], C1[19], C1[17], C1[16], C2[19], C2[18], C2[15], C2[14], 
   Dashed[16, 17], Dashed[15, 19], Dashed[14, 18], Dashed[15, 17], 
   Dashed[14, 16], OV[8, 11, 13], OV[7, 10, 12], OV[4, 9, 13], OV[3, 9, 12], 
   OV[1, 6, 11], OV[2, 5, 10]]}