r,c = map(int,input().split())
masume = [[0 for i in range(c)] for j in range(r)]
for i in range(r):
	masume[i] = list(input())

thispoint = True
for ri in range(r):
	for ci in range(c):
		if masume[ri][ci] == '#':
			draw = False
			for ar in [-1,0,1]:
				for ac in [-1,0,1]:
					if abs(ar) == abs(ac):
						continue
					chkr = ri + ar
					chkc = ci + ac
					if chkr >= 0 and chkr < r and chkc >= 0 and chkc < c and masume[chkr][chkc] == '#':
						draw = True
						break
			if draw:
				break
			if not(draw):
				thispoint = False
				break
	if not(thispoint):
		break
if thispoint:
	print('Yes')
else:
	print('No')