#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
#include <queue>
#include <deque>
#include <set>

using namespace std;

void NO() {
	cout << "NO";
	exit(0);
}

struct Node
{
	char color = 'w';
	bool use = false;
	set<int> dec;
	set<int> anc;
	vector<int> edges;
};
vector<Node> g;

int useCnt;

set<int> DFS(int u)
{
	g[u].color = 'g';

	set<int> res;

	for (int v : g[u].edges)
	{
		if (g[v].color != 'w') NO();

		auto cur = DFS(v);
		for (auto i : cur) res.insert(i);
		res.insert(v);
	}

	g[u].color = 'b';

	if (g[u].dec != res) NO();
	return res;
}

int main()
{
	//freopen("input.txt", "r", stdin);
	map <int, set<int>> lvls;
	int n;
	cin >> n;
	g.resize(n);

	int root = -1;
	for (int u = 0; u < n; ++u) {
		int len;
		cin >> len;
		while (len--) {
			int v;
			cin >> v;
			--v;
			g[u].dec.insert(v);
			g[v].anc.insert(u);
		}
		if (g[u].dec.size() == n - 1)
		{
			if (root != -1) NO();
			root = u;
		}
	}

	if (root == -1)	NO();

	lvls[0].insert(root);
	g[root].use = ++useCnt;
	int lvl = 0;
	for (int i = 0; i < n; ++i)
		g[i].anc.erase(root);

	map <int, int> last;

	for (auto i : g[root].dec) {
		last[i] = root;
	}

	vector <pair<int, int>> sol;

	while (useCnt < n) {
		lvl++;
		for (int u = 0; u < n; ++u) {
			if (!g[u].use && g[u].anc.empty()) {
				auto it = last.find(u);
				if (it==last.end()) NO();
				else {
					sol.emplace_back(it->second, u);
					g[it->second].edges.push_back(u);
				}
				lvls[lvl].insert(u);
				g[u].use = ++useCnt;
			}
		}
		if (lvls[lvl].empty()) NO();
		last.clear();
		int sumsize = 0;
		for (auto u : lvls[lvl]) {
			for (int j = 0; j < n; ++j) {
				g[j].anc.erase(u);
			}
			for (auto j : g[u].dec) {
				if (g[j].use) NO();
				last[j] = u;
				sumsize++;
			}
		}
		if (!(last.size() == sumsize && n - useCnt == last.size())) NO();
	}

	if (DFS(root).size() != n - 1) NO();
	for (auto u : g) if (u.color != 'b') NO();

	cout << "YES" << endl;
	for (auto i : sol) {
		cout << i.first+1 << ' ' << i.second+1 << endl;
	}

    return 0;
}