6Pappano L. The Year of the MOOC[J]. The New York Times, 2012,2(12): 2012.
7Steiner K C,Kunsman J R.Dendrology education in the Unit- ed States[J].Joumal of Forestry,1979,77(5): 289-291.
8Kellogg S. Online learning: How to make a MOOC[J].Nature, 2013,499(7458):369-371.
9Robinson A C, Kerski J, Long E C, et al. Maps and the geospatial revolution: teaching a massive open online course (MOOC) in geography[J]. Journal of Geography in Higher E- ducation, 2015, 39(1): 65-82.
10Gamage D, Fernando S, Perera I. Quality of MOOCs: A re- view of literature on effectiveness and quality aspects[J]. E- ducation, 2015(121): 2.