| Diffraction by an Acoustic Grating Perturbed by a Bounded Obstacle Recent countries visiting this post |  |
 | 1 | United States |
 | 1 | Ukraine |
 | 1 | Russian Federation |
| Diffraction by an Acoustic Grating Perturbed by a Bounded Obstacle Recent countries visiting this post | |
| 1 | United States |
| 1 | Ukraine |
| 1 | Russian Federation |