no. 2
Homotopy negligible subsets
Compositio Mathematica, Tome 21 (1969) no. 2, pp. 155-161. 
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     author = {Eells, Jr., James and Kuiper, Nicolaas H.},
     title = {Homotopy negligible subsets},
     journal = {Compositio Mathematica},
     pages = {155--161},
     publisher = {Wolters-Noordhoff Publishing},
     volume = {21},
     number = {2},
     year = {1969},
     mrnumber = {253331},
     zbl = {0181.51401},
     language = {en},
     url = {http://archive.numdam.org/item/CM_1969__21_2_155_0/}
}
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Eells, Jr., James; Kuiper, Nicolaas H. Homotopy negligible subsets. Compositio Mathematica, Tome 21 (1969) no. 2, pp. 155-161. http://archive.numdam.org/item/CM_1969__21_2_155_0/

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