# Houston Problem Book Problem 7

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** Problem 7 (HPB):** Is it true that the rim-type of any real curve (or half-ray curve) curve is at most $3$? (Asked by A. Lelek, 09/29/71)

**Answer:** Yes. A solution follows from Nadler's work. (W. Kuperberg and P. Minc, 03/28/79)