INVESTIGATION OF SEAWATER INTRUSION IN SHABLA-KRAPETS REGION, NE BULGARIA

Danchev D., Damyanov At., Nikolov E., Velinov V., Andonova G. Hydrogeological study of groundwater in Bulgaria and compilation of a hydrogeological map for zoning according to water abundance in Southern Dobrudja and Ludogorie, Summary updated report, Contract � 764, Sofia, 1977. (Personal contact) In Bulgarian

Galabov M., Penchev P., Velikov B., Damyanov A., Development of measures to protect the aquifers near the Black Sea from pollution due to the seawater intrusion, Contract � 1130, 1989. (Personal contact) In Bulgarian

Pentchev P., A general assessment of the seawater intrusion in the Sarmatian karst aquifer: Geology and Mineral Resources, 9-10, p, 19-23, 1996. (In Bulgarian)

Pentchev P., Consultancy services in connection with the project: Integrated Management of Transboundary Groundwater between Bulgaria and Romania in Dobrudja/Dobrogea Area - Technical Assistance to ensure transboundary groundwater management using the WFD and Groundwater Directive, EuropeAid/122633/D/SER/BG), EPTISA Servicios de Ingenieria, S, A, 2007. (Personal Contract)

Pentchev P., Velichkov V., Velichkova B. Carrying out exploratory monitoring to establish the sources of pressure in the event of a worsening in the state of the groundwater body in the Krapets - Shabla - Tyulenovo region of seawater intrusion, Contract - �370/09,05, Sofia, 2017 (Personal Contract) In Bulgarian

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Pulido Bosch, A., Machkova, M., Lopez-Chikano, M., Calvache, M.L., Dimitrov, D., Calaforra, J.M., Velikov, B. and Penchev, P., Hydrogeology of the Upper Aquifer, Dobrich Region (Northeastern Bulgaria), Hydrogeology Journal, Vol 5, No 2, p.75-85, 1997. DOI: 10.1007/s100400050120

Pulido-Bosch, A. (Principal contractor), Dimitrov, D., Machkova, M., Pentchev, P., Velikov, B., (Subcontractors), Ecological Problems of Karst Waters Caused by Overexploitation and Contamination (1994 -1996), Fixed Contribution Contract No. CIPA-CT93-0139 between the European Economic Community and the University of Granada, Spain, 1996.