- Fitze, K., M. Maksimovic, and J. Spaic. 1962. Die chemische Bekampfung der Borkenkafer [In Serbian, French summary]. Gugoslovenski savetodavni centar za poljoprivredu i sumatstvo, Beograd. 32 p., 9 figs.
- Spaic, I. 1955. Problematika zastite suma u NR Hrvatskoj . Sumarski List 79:440-468.
- Spaic, I. 1956. Suzbijanje potkornjaka zatrovanim lovnim stablima [Control of barkbeetles by means of poisoned trap-trees] . Sumarski List 80:86-101.
- Spaic, I. 1964a. Pokusi suzbijanja potkornjaka na alepskom boru metodom prstenovanja [Experimental control of bark-beetles on Pinus halepensis using the osmosis method] . Sumarski List 88:226-236.
- Spaic, I. 1964b. The susceptibility of ash to attack by Hylesinus fraxini [In Serbian, German summary] . Sumarski List 88:10-21.
- Zivojinovic, S., K. Vasic, and I. Spaic. 1962. Zastita centinara. I deo. Zastita od stetnih insekata [In Serbian]. Jugoslavia Saverzni cent. za Poljoprivrede i sum. 1962. 176 p.