@article{Wild2013, 
     author = "Wild, Marcel", 
     doi = "10.1007/s11083-013-9292-6", 
     issn = "0167-8094", 
     journal = "Order", 
     link = "http://link.springer.com/10.1007/s11083-013-9292-6", 
     month = "apr", 
     number = "1", 
     pages = "121--135", 
     title = "Output-Polynomial Enumeration of All Fixed-Cardinality Ideals of a Poset, Respectively All Fixed-Cardinality Subtrees of a Tree", 
     uri = "http://link.springer.com/10.1007/s11083-013-9292-6", 
     volume = "31", 
     year = "2013", 
}

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