H, W = map(int,input().split())
src = [list(input()) for i in range(H)]

dxy = [(-1,-1),(-1,0),(-1,1),(0,-1),(0,1),(1,-1),(1,0),(1,1)]

for h in range(H):
  for w in range(W):
    count = 0
    for dx,dy in dxy:
      count += 1
      if w + dx < 0 or w + dx > W-1 or h + dy < 0 or h + dy > H-1:
        continue

      if src[h + dy][w + dx] == "#":
        print("Yes")
        exit()
      
      if count == 8:
        print("No")
        exit()