Reference number | Author | Publication year | Country | Samples |
---|
[1] | Yu et al. | 2011 | China | 154 |
[5] | Deng et al. | 2013 | China | 115 |
[6] | Gai et al. | 2012 | China | 59 |
[7] | Sun et al. | 2012 | China | 59 |
[8] | Ding et al. | 2014 | China | 59 |
[9] | Liu et al. | 2013 | China | 311 |
[10] | Zhang et al. | 2012 | China | 49 |
[32] | Cui et al. | 2013 | China | 16 |
[33] | Wen et al. | 2014 | China | 22 |