वायु गुणवत्ता डेटा प्रदानकर्ता: the Weather Underground (wunderground.com) and the China National Urban air quality real-time publishing platform (全国城市空气质量实时发布平台) (113.108.142.147:20035) and the Helongjiang Environmental Protection Agency (黑龙江省空气质量实时发布平台) (hljdep.gov.cn)