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Type	Originator	Title	Date
	Jugoslavenska Akademija Znanosti Zagreb	Acta Geologica Vol 3,Knjiga 31	1961
	Warwick,Gordon T	Cave Deposits & Palaeoclimatology	1961
	Powell,R.L	Caves of Indiana	1961
	Hogg,G	Deep down	1961
	Symp.Int.di Speleologia	Diff.e Data.del Fenomo Carsico Nella Penisola Sorrentina	1961
	Mugnier,C	Distinction entre Trois Types D'eboulis Cryoclast.dans les Cav.	1961
	Lansing,A	Endurance	1961
	Polska Akademia,Warsaw	Folia Quaternaria	1961
	Serban,M, Viehman,I & Coman,D	Grottes de Roumanie	1961
		Karst Und Hohlenkunde(2 Heft 1961)	1961
		Karst Und Hohlenkunde(2 Heft 1961)	1961
	Symp.Int. di Speologia	Les Formations Pedologiques de la Grotte des Perles	1961
	Basham,R Dilly,M Dilly,N Hawes,L.A & Rigden,B	OFD Ogof Ffynnon Ddu - S1065- Cwm Dwr	27/02/1961
	Gilchrist Shirlaw,D.W et al.	Soilsurvey of Tauorga, Tripolitania, Libya	1961
	Mitchell,W.R	The Hollow Mountains	1961
	Thomas,Trevor M	The Mineral Wealth of Wales and its Exploitation	1961
	Trimmel,H	Un Die Frage der Hohlenbildungszyklen	1961