H, W = [int(i) for i in input().split()]
list = [list(input()) for i in range(H)]
dx = [-1, 0 , 1]
dy = [-1, 0 , 1]
flg = True
for i in range(H):
    for j in range(W):
        count = 0
        if list[i][j] == ".":
            continue
        if list[i][j] == "#":
            for l in dx:
                for m in dy:
                    if (i + l < 0) or (i + l > H -1) or (j + m < 0) or (j + m > W -1) or l + m == 0:
                        continue
                    if list[i + l][j + m] == "#":
                        count += 1
        if count == 0:
            flg = False
if flg:
    print("Yes")
else:
    print("No")