Add comment on k-corona v k-shell
Add comment on k-corona v k-shell

Fiexes #684

ltiao/networkx,ionanrozenfeld/networkx,kernc/networkx,ghdk/networkx,debsankha/networkx,farhaanbukhsh/networkx,farhaanbukhsh/networkx,yashu-seth/networkx,debsankha/networkx,jcurbelo/networkx,tmilicic/networkx,jtorrents/networkx,beni55/networkx,nathania/networkx,kernc/networkx,chrisnatali/networkx,ionanrozenfeld/networkx,dmoliveira/networkx,kai5263499/networkx,bzero/networkx,JamesClough/networkx,kai5263499/networkx,harlowja/networkx,harlowja/networkx,aureooms/networkx,blublud/networkx,bzero/networkx,chrisnatali/networkx,jni/networkx,michaelpacer/networkx,goulu/networkx,dhimmel/networkx,wasade/networkx,ionanrozenfeld/networkx,RMKD/networkx,dhimmel/networkx,cmtm/networkx,kai5263499/networkx,NvanAdrichem/networkx,aureooms/networkx,SanketDG/networkx,dhimmel/networkx,OrkoHunter/networkx,chrisnatali/networkx,sharifulgeo/networkx,jni/networkx,blublud/networkx,bzero/networkx,aureooms/networkx,jakevdp/networkx,farhaanbukhsh/networkx,jakevdp/networkx,RMKD/networkx,nathania/networkx,sharifulgeo/networkx,nathania/networkx,jni/networkx,kernc/networkx,jakevdp/networkx,ghdk/networkx,andnovar/networkx,Sixshaman/networkx,jtorrents/networkx,dmoliveira/networkx,ghdk/networkx,dmoliveira/networkx,blublud/networkx,debsankha/networkx,sharifulgeo/networkx,jfinkels/networkx,RMKD/networkx,harlowja/networkx