This unusual book on the strength of the atom was published in Slovak language in 1958 in Bački Petrovac in Serbia, at the time in Yugoslavia, a town with a largely Slovak population. The book explaining laws of physics to children with text, accompanied with large illustrations in black and orange, was printed and illustrated in Slovenia, in the north of Yugoslavia.
The Serbian town Bački Petrovac was populated with Slovaks in 1745 and remains until today inhabited with mostly Slovak speaking population.
The illustrator was Stane Kumar (1910-1997), a Slovenian artist, born in Trieste. Kumar studied history of art and archeology, and later art under Ljubo Babić and Krsto Hegedušić in Zagreb. A left-wing activist and socialist, he was imprisoned at the Gonars concentration camp during WWII by the Fascists. After WWII, Stane Kumar decicared himself mostly to painting and graphic design. His favourite subjects came from the world of technology, mostly from the world of railroads and trains.
The book was printed in 1000 examples. We could only trace 2 institutional copies worldwise (Ljubljana City Library, National and University Library; OCLC 440746551).
References: Krečič, Peter: Kumar, Stane (1910–1997). Slovenska biografija. Slovenska akademija znanosti in umetnosti, Znanstvenoraziskovalni center SAZU, 2013. http://www.slovenska-biografija.si/oseba/sbi1016510/#primorski-slovenski-biografski-leksikon (28. julij 2018). Izvirna objava v: Primorski slovenski biografski leksikon: 9. snopič Križnič - Martelanc, 2. knjiga. Ur. Martin Jevnikar Gorica, Goriška Mohorjeva družba, 1983.