《资治通鉴·后梁纪·后梁纪四》
贝州刺史张源德有三千士卒，每天夜晚出去抢劫，贝州人民甚为痛苦，请求李存审挖沟阻止他们出城骚扰，以使人民能安居耕耘。
张源德有卒三千，每夕分出剽掠，州民苦之，请堑其城以安耕耘。
The Prefect of Beizhou, Zhang Yuande, had 3,000 soldiers who went out to rob every night, causing great suffering for the people of Beizhou, who begged Li Cunxian to dig a trench to prevent them from leaving the city to harass them and to allow the people to cultivate their fields in peace.