In , Lemma 3.2 guaranteed the monotonicity of regular solutions of (1.4) on some fixed interval near the origin in terms of initial values, so as to prove the existence of singular solutions of (1.1). To make the arguments more clear for readers, the estimate of g(t) on page 295, line 23 in the original proof of Lemma 3.2 needs to be modified. Here, we provide a revised statement and proof of this lemma, and add an extra remark in the following. Refer to  for all notations and labeled equations appearing below.
All Science Journal Classification (ASJC) codes
- Applied Mathematics