Published above 100 articles, reports and monographs on principle problems of Engineering Geology, Engineering-Geological, Hydrogeological, Seismic Mapping and Zoning, Physico-mechanical properties of rocks and soils,Geological Hazards, Landslides, Earthquakes phenomena,Engineering-Geological conditions and Environment, Geomonitoring,Engineering-Geological problems of monuments and ancient works, Historical cases.

Selected publications:

Antonov H., N.Boyadjiev, D.Danchev, Il.Iliev, P.Petrov, N.Plotnikov. 1962.Hydrogeological Subdivision of Bulgaria. Works on the Geology of Bulgaria,Ser.Eng.Geol.& Hydrogeol., 1: 212 p. (in Bulgarian).

Kamenov, B. & I.Iliev 1963. Engineering-geological zoning of Bulgaria. Works on the Geology of Bulgaria, Ser.Eng.Geol.& Hydrogeol., 2: 5-123 (in Bulgarian).

Kamenov B., Il.Iliev, E.Avramova, M.Galabov, Tz.Stancheva. 1963.Engineering-Geological Map of Bulgaria in scale 1:500,000. Sofia, Publ.House. of Bulg.Acad.Sci.

Iliev, Il. 1967. On the some regularities in the distribution of the landslides and seismic regions in the country. Review of the Bulg. Geol.Soc., 27, No.1, 88-93 (in Bulgarian).

Kamenov, B., Il.Iliev, St.Tzvetkov, E.Avramova, G.Simeonova. 1973. Influence of the geological structure on the occurrence of different types of landslides along the Bulgarian Black Sea Coast. Proc. Conf. on Nat. Slopes Stability and Conservation, Naples, Italy, Geol. applicata a idrogeologia,Vol. VIII, Parte I, 209-220.

Iliev, Il. 1974. Features of the landslides caused by earthquakes. Bull.Geol. Inst, Ser. Eng. Geol. and Hydrogeol., Vol. 23, 161-166 (in Bulgarian).

Kamenov B. and Il.Iliev. 1974. Map of the Engineering-Geological Elements in Bulgaria in scale 1:1,000,000. Proc. of the Seminar on the Seismotectonic Map of the Balkan Region, Dubrovnik, April 17-24, 1973, UNESCO, Skopje.

Iliev, Il. 1977. On the compilation of an Engineering-Geological Map of Slope Movements in Europe. Proc. of the Symp. Landslides and other Mass Movements, Praha, Czechoslovakia, Sept. 15-16, 1977, Bull. IAEG, No.16, 33-34.

Kamenov, B., I.Iliev, E.Avramova-Taceva 1977. Conditions for the origin,mechanism and dynamics of block landslides in Bulgaria. Bull. IAEG, 16: 98-101.

Iliev Il. 1978. Slope Deformation Phenomena Caused by Earthquakes. Proc. 3rd Congr. IAEG, Madrid, Vol. VIII, 7-14.

Brankov G. (ed.) 1983. Vrancea - 1977. Aftereffects in Bulgaria. Publ. House of BAS, 428 pp.

Iliev, Il. & D.Stoikov. 1984. Ingenieurengeologische verhaltnisse im Rutschungsgebiet nordlich von Varna. Untersuchungen zur geod‰tische Bestimung von Rutschungserscheinungen und vertikalen Krustenbewegungen,No.133, W.A.F.V. Univ. Hannover, 185-197.

Iliev Il. 1990. Compiling of special engineering-geological maps. Proc. 6th Int. Congr. IAEG, Amsterdam, Aug. 6-10, Balkema,Vol. 1, 39-44.

Tzvetanov Pl. (ed.) 1990. NPS-Belene. Investigations and Standpoint of the Bulgarian Academy of Sciences. Publ. House of BAS, 412 pp.

Frangov,.,P.Ivanov,N.Dobrev & I.Iliev. 1992. Stability problems of the rock monument "Madara horseman". In: Proc. of the 7th Int. Congr. on Deterioration and Conservation of Stone, Lisboa, Portugal, 1425-1435.

Iliev-Broutchev, I. (ed.), G.Frangov, N.Dobrev, P.Ivanov, D.Evstatiev,A.Bozhinova, D.Karastanev,K.Todorov, R.Angelova, B.Ranguelov,J.Karagyuleva, P.Petrov, G.Alexiev, Ch.Mladenov, B.Manchev, D.Boykov &P.Mechkarski. 1994. Map of the Geological Hazards in Bulgaria. Scale 1:500,000 and Explanatory Text.. Military Topographic Service, Troyan and Publ. House of Bulg. Acad. Sci., Sofia (in Bulgarian, Summary in English).

Christoskov L., D.Gergova, Il.Iliev, V.Rizzo. 1995. Traces of seismic effects on archaeological sites in Bulgaria. Annali di Geofisica, Vol.XXXVIII, No.5-6,Nov.-Dec., 907-918.

Gergova D., Il.Iliev, V.Rizzo. 1995. Evidence of a seismic event on Thracian tombs dated to Hellenistic period (Sveshtari, NE Bulgaria). Annali di Geofisica, Vol. XXXVIII, No.5-6, Nov.-Dec., 919-926.