h, w = map(int, input().split())
s = [list(input()) for i in range(h)]
S1 = [[0] * (w+2) for i in range(h+2)]
for i in range(h):
    for j in range(w):
        if s[i][j] == "#":
            S1[i+1][j+1] = 1
S2 = [[0] * w for i in range(h)]
for i in range(h):
    for j in range(w):
        if s[i][j] == "#":
            S2[i][j] = S1[i][j+1] + sum(S1[i+1][j:j+3]) + S1[i+2][j+1]
if 1 in S2:
  print("No")
else:
  print("Yes")