Models of rubric: Others Model 347 Tetrahedron in the projective space Model 365 Large frustum of pyramid Model 377 Two-sided surface with the clover leaf sling as boundary curve Model 392 Wooden ring with 7 neighbouring areas Model 392 Wooden ring with 7 neighbouring areas Model 408 Clover leaf sling on torus Model 408 Clover leaf sling on torus Model 464 Model of a clover leaf sling with singularity-free surface Model 465 3-times twisted Möbius strip with clover leaf sling as border Model 522 Three rings that are devoured with each other, but not pairwise