import Control.Monad

main = do
    (h:w:_) <- (fmap read . words) <$> getLine
    input <- replicateM h getLine
    let matrix = replicate (w+2) '.':(map (\xs->'.':(xs++".")) input)++[replicate (w+2) '.']
    let answer = and [ check matrix i j | i<-[1..h], j<-[1..w] ]
    if (answer)
        then putStrLn "Yes"
        else putStrLn "No"

check :: [String] -> Int -> Int -> Bool
check str i j
    | (str!!i)!!j == '.' = True
    | otherwise = or [(str!!i')!!j' == '#' | i'<-[i-1,i+1], j'<-[j-1,j+1]]