Macan, T. T. <br/><br/>
A key to the British fresh - and brackish - water gastropods :  with notes on their ecology / 
by T. T. Macan illustrated by the late R. Douglas Cooper. 
 - Fourth edition. 
 - [s. l] :  Freshwater Biological Association,  1977. 
 - 46 p. :  ill. ;  23 cm. 
<br/><br/><label>Subjects--Geographic Terms: </label><br/>Gastropoda--United Kingdom.