#include <bits/stdc++.h>
int main() {
  int H, W;
  scanf("%d %d", &H, &W);
  char masu[52][52];
  int i, j;
  for (i = 0; i <= 51; i++) {
    for (j = 0; j <= 51; j++) {
      masu[i][j] = '.';
    }
  }
  for (i = 1; i <= H; i++) {
    for (j = 1; j <= W; j++) {
      scanf("%s", &masu[i][j]);
    }
  }
  int canyou = 1;
  for (i = 1; i <= H; i++) {
    for (j = 1; j <= W; j++) {
      if (masu[i][j] == '#') {
        if (masu[i - 1][j] == '#' || masu[i + 1][j] == '#' ||
            masu[i][j - 1] == '#' || masu[i][j + 1] == '#') {
        } else {
          canyou = 0;
          printf("%d %d\n", i, j);
        }
      }
    }
  }
  if (canyou == 1)
    printf("Yes");
  else
    printf("No");
  return 0;
}
