- Wave equation | 124, 418, 16
- Important partial differential equation | 43, 793, 24
- Partial differential equation | 0, 2k, 45
- Differential equation | 0, 3k, 69
- Calculus | 17, 8k, 203
- Mathematics | 17, 28k, 633
- Ciro Santilli's Homepage | 262, 218k, 4k
- History of quantum mechanics | 488, 488, 1