Results of ¹²CO survey around the six LHAASO UHE sources. The data in panel (a) was integrated with a LSR velocity coverage from –4.9 km s⁻¹ to 1.6 km s⁻¹, covering the MC in proximity to J0007+5659u. For the data in panels (b)–(d), the LSR velocity integrating range was ±47.1 km s⁻¹, reaching the limitation of this survey (Dame & Thaddeus 2022). The positions of the six LHAASO sources are marked by yellow dashed circles with radius of 0$\stackrel{°}{.}$5. The MC proposed to be associated with J0007+5659u is indicated by the dashed box in light green.