h,w = map(int, input().split())
original = [list(input()) for _ in range(h)]
for i in range(h-1):
  for j in range(w-1):
    if original[i][j]=='#' and original[i-1][j]!='#' and original[i+1][j]!='#' and original[i][j-1]!='#' and original[i][j+1]!='#':
      print(i,j)
      print('No')
      exit()
      
print('Yes')