Petrov, K., Ivanov, J. Problems in the Constructions of Landfills and Their Impact on the Socio-Economic Development of the Regions. Sofia: Издателски комплекс - УНСС, 31-36,.
Petrov, K., Ivanov, J. Problems in the Constructions of Landfills and Their Impact on the Socio-Economic Development of the Regions. Sofia: Издателски комплекс - УНСС, 31-36,.
Petrov, K., Ivanov, J. Problems in the Constructions of Landfills and Their Impact on the Socio-Economic Development of the Regions, Sofia: Издателски комплекс - УНСС 31-36,.
Petrov, K., & Ivanov, J. Problems in the Constructions of Landfills and Their Impact on the Socio-Economic Development of the Regions. Trends in Regional Development and Security Management : International Scientific Conference : 4 - 6 October 2018 (с. 31-36). Sofia: Издателски комплекс - УНСС.
Petrov K, Ivanov J. Problems in the Constructions of Landfills and Their Impact on the Socio-Economic Development of the Regions. Sofia: Издателски комплекс - УНСС; p. 31-36.