/* -*- coding: utf-8 -*-
 *
 * 1805.cc:  No.1805 Approaching Many Typhoon - yukicoder
 */

#include<cstdio>
#include<vector>
#include<queue>
#include<algorithm>
 
using namespace std;

/* constant */

const int MAX_N = 2000;

/* typedef */

typedef vector<int> vi;
typedef queue<int> qi;

/* global variables */

vi nbrs[MAX_N];
bool ds[MAX_N], fs[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, m, st, gl;
  scanf("%d%d%d%d", &n, &m, &st, &gl);
  st--, gl--;

  for (int i = 0; i < m; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--, v--;
    nbrs[u].push_back(v);
    nbrs[v].push_back(u);
  }

  int un;
  scanf("%d", &un);

  for (int i = 0; i < un; i++) {
    int ii;
    scanf("%d", &ii), ii--;
    fs[ii] = true;
  }

  ds[st] = true;
  qi q;
  q.push(st);

  while (! q.empty()) {
    int u = q.front(); q.pop();

    for (auto v: nbrs[u])
      if (! ds[v] && ! fs[v]) {
	ds[v] = true;
	q.push(v);
      }
  }

  if (ds[gl]) puts("Yes");
  else puts("No");
  return 0;
}