#include <bits/stdc++.h>
using namespace std;
int main() {
  int H, W;
  cin >> H >> W;
  vector<string> grid(H);
  for (int i = 0; i < (int)(H); ++i) cin >> grid[i];
  string res = "Yes";
  for (int i = 0; i < (int)(H); ++i)
    for (int j = 0; j < (int)(W); ++j) {
      if (grid[i][j] == '.') continue;
      res = "No";
      for (int k = -1; k <= 1; ++k) {
        if (i + k < 0 || i + k >= H) continue;
        for (int l = -1; l <= 1; ++l) {
          if (j + l < 0 || j + l >= W) continue;
          if (k == 0 && l == 0) continue;
          if (grid[i + k][j + l] == '#') res = "Yes";
        }
      }
      if (res == "No") break;
    }
  cout << res << endl;
}
