Battle of Songzhou (638) — the same event in New Book of Tang and Zizhi Tongjian

New Book of Tang: Tibet invaded Songzhou; Hou Junji was made Grand General of the Dangmi Route to campaign against them, and the next month Niu Jinda…

What each source says

New Book of Tang (Xin Tangshu), Annals · AD 638 · 松州

Tibet invaded Songzhou; Hou Junji was made Grand General of the Dangmi Route to campaign against them, and the next month Niu Jinda defeated them at Songzhou.

吐蕃寇松州,侯君集為當彌道行軍大總管
Location: 新唐書 卷002 太宗 貞觀12年8月

Zizhi Tongjian (Comprehensive Mirror) · AD 638 · 松州

In 638, the Tubo attack the city for more than ten days; Niu Jinda, as vanguard, strikes in September (Xinhai day) while the defenses are unready, routs the Tubo beneath the walls of Songzhou, and beheads more than a thousand.

吐蕃攻城十餘日,進達為先鋒,九月,辛亥,掩其不備,敗吐蕃於松州城下,斬首千餘級。
Location: 권195 638년 항

Place: 松州

Show on the map — open New Book of Tang (Xin Tangshu), Annals