import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        int m = sc.nextInt();
        int start = sc.nextInt() - 1;
        int goal = sc.nextInt() - 1;
        int[] lefts = new int[m];
        int[] rights = new int[m];
        for (int i = 0; i < m; i++) {
            lefts[i] = sc.nextInt() - 1;
            rights[i] = sc.nextInt() - 1;
        }
        int u = sc.nextInt();
        HashSet<Integer> ngs = new HashSet<>();
        for (int i = 0; i < u; i++) {
            ngs.add(sc.nextInt() - 1);
        }
        UnionFindTree uft = new UnionFindTree(n);
        for (int i = 0; i < m; i++) {
            if (!ngs.contains(lefts[i]) && !ngs.contains(rights[i])) {
                uft.unite(lefts[i], rights[i]);
            }
        }
        if (uft.same(start, goal)) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
    
    static class UnionFindTree {
        int[] parents;
        
        public UnionFindTree(int size) {
            parents = new int[size];
            for (int i = 0; i < size; i++) {
                parents[i] = i;
            }
        }
        
        public int find(int x) {
            if (x == parents[x]) {
                return x;
            } else {
                return parents[x] = find(parents[x]);
            }
        }
        
        public boolean same(int x, int y) {
            return find(x) == find(y);
        }
        
        public void unite(int x, int y) {
            if (!same(x, y)) {
                parents[find(x)] = find(y);
            }
        }
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        if (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}