http://www.mathworksheetsland.com/7/2recogprop.html

http://warmup.nwea.org/sample_tests/map_math_educator.html

https://www.mathsisfun.com/improper-fractions.html

http://centros4.pntic.mec.es/~deprac15/iglessandra/sexto/PRESENT%20SIMPLE,%20superguay.pdf