Hald-Mortensen , P. 1970. Knopsvanen. [Mute Swans.] Feltornithologen 12: 

 73-76. [In Danish. ] 



1969 



Chang, P. W., M. C. Perry and V. Jasty. 1969. Fibroma in a Mute Swan. J. Am. 

 Vet. Med. Assoc. 155: 1039. 



Kraus , M. and A. Gauckler. 1969. Zur Ausbreitung des Hockerschwans ( Cygnus 

 olor ) in Nordbayern. [The breeding population of Mute Swans in northern 

 Bavaria.] Anz. Ornithol. Ges. Bayern 8: 452-462. [In German with English 

 summary. ] 



Perrins, C. M. 1969. Mute Swan's method of disposing of broken egg. Brit. 

 Birds 62: 383. 



Reese, J. G. 1969. Mute Swans breeding in Talbot County, Maryland. Md. Bird- 

 life 25: 14-16. 



Yates, V. J., L. T. Miller, V. Jasty, C. H. Willey and M. Holtzinger. 1969. 



Web necrosis in Mute Swans a report of an outbreak. Bull. Wildl. Dis. 



Assoc. 5: 33-34. 



1968 



Berndt , R. 1968. Der Hockerschwan ( Cygnus olor ) als Geleplundermr und Jung- 

 vogelrauber. Intern. Rat Vogelschutz Sektion 8: 51-52. [In German.] 



Jogi, A. 1968. [The present distribution of the Mute Swan in the Estonian 



S.S.R. ] Communs. Baltic Commiss. Study Bird Migr. 5: 74-79. [In Russian 

 with English summary.] 



Minton, C. D. T. 1968. Pairing and breeding of Mute Swans. Wildfowl 19: 41-60. 



Munro, R. E. , L. T. Smith and J. J. Kupa. 1968. The genetic basis of color 

 differences observed in the Mute Swan ( Cygnus olor ). Auk 85: 504-505. 



Willey, C. H. 1968a. The ecology, distribution and abundance of the Mute Swan 

 ( Cygnus olor ) in Rhode Island. M.S. thesis, Univ. Rhode Island/Kingston, 

 RI. 93 pp. 



. 1968b. The ecological significance of the Mute Swan in Rhode Island. 



Proc. N.E. Fish & Wildl. Conf . 23 pp. 



1967 



Harrison, J. G. and M. A. Ogilvie. 1967. Immigrant Mute Swans in south-east 

 England. Wildfowl Trust Annu. Rept . 18: 85-87. 



Jensen, F. 1967. Knopsvanen ( Cygnus olor ) som ynglefugl ved Bognaes . [The 

 Mute Swan Cygnus olor breeding at Bognaes.] Dan. Ornithol. Foren. 

 Tidsskr. 61: 143-150. [In Danish with English summary.] 



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