"use strict"

const main = arg => {
  arg = arg.trim().split("\n");
  const H = parseInt(arg[0].split(" ")[0]);
  const W = parseInt(arg[0].split(" ")[1]);
  
  const tiles = arg.slice(1, H + 1).map(n=>n.split(""));
  
  const nx = [1, 0, -1, 0];
  const ny = [0, 1, 0, -1];
  
  for(let i in tiles) {
      for(let j in tiles[i]) {
          let cnt = 0;
          
          for(let k=0; k<4; k++) {
              let dx = nx[k] + parseInt(j);
              let dy = ny[k] + parseInt(i);
              
              if(dy < 0 || dy > H - 1) continue;
              if(dx < 0 || dx > W - 1) continue;
             
              console.log("k:" + k);
              console.log("nx[k]:" + nx[k]);
              console.log("dx:" + dx);
              console.log("dy:" + dy);
              console.log("---------");
              
              if(tiles[dy][dx] === ".") {
                  cnt++;
              }
          }
          
          if(tiles[i][j] === "#" && cnt === 4) {
              console.log(i);
              console.log(j);
              console.log("No");
              return;
          }
      }
   }
   
   console.log("Yes");
}

main(require("fs").readFileSync("/dev/stdin", "utf8"));
