#include <bits/stdc++.h>
using namespace std;
int main() {
  int H, W;
  cin >> H >> W;
  vector<vector<char>> B(H, vector<char>(W));
  for (int i = 0; i < H; i++) {
    for (int j = 0; j < W; j++) {
      cin >> B.at(i).at(j);
    }
  }
  int dx[] = {1, 1, 0, -1, -1, -1, 0, 1};
  int dy[] = {0, 1, 1, 1, 0, -1, -1, -1};
  bool flag0 = true;
  for (int i = 0; i < H; i++) {
    for (int j = 0; i < W; j++) {
      if (B.at(i).at(j) == '#') {
        bool flag = false;
        for (int k = 0; k < 8; k++) {
          int a = i + dx[k];
          int b = j + dy[k];
          if (0 <= a && a <= H - 1 && 0 <= b && b <= W - 1 &&
              B.at(a).at(b) == '#') {
            flag = true;
          }
        }
        if (!flag) {
          flag0 = false;
          break;
        }
        break;
      } else {
        continue;
      }
    }
  }
  if (flag0) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return 0;
}
