Radek KuchtaRadimir VrbaJaroslav KadlecMichal PavlikOpen Internet Portal for Elementary and High Schools.180-1832009ICDShttps://doi.org/10.1109/ICDS.2009.38https://doi.ieeecomputersociety.org/10.1109/ICDS.2009.38conf/icds/2009db/conf/icds/icds2009.html#KuchtaVKP09