The classical Bertrand-Darboux problem
2008 ◽
Vol 151
(4)
◽
pp. 3230-3244
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Keyword(s):
2021 ◽
2012 ◽
Vol 55
(1)
◽
pp. 197-205
◽
1996 ◽
Vol 37
(3)
◽
pp. 354-391
◽
Keyword(s):
2013 ◽
Vol 49
(12)
◽
pp. 1577-1595
◽
1999 ◽
Vol 71
(2)
◽
pp. 171-193
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