About this article
Published Online: Jun 28, 2019
Page range: 163 - 168
Received: Nov 28, 2018
Accepted: May 10, 2019
DOI: https://doi.org/10.2478/AMNS.2019.1.00016
Keywords
© 2019 S. Goyal et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
Fig. 1
![The graphs G, H, G[H]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/64709ef171e4585e08aa18b4/j_AMNS.2019.1.00016_fig_001.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6AP2G7AKOUXAVR44%2F20251005%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251005T042202Z&X-Amz-Expires=3600&X-Amz-Signature=b4679458c6e2af8e9fa537a89b7ce4d2577ac2cf22a90cf398230a11fdd2be9c&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 2

Fig. 3
![The graphs G, P = Λ(G), Q = Λ[G], R = D2(G) and S = D2[G]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/64709ef171e4585e08aa18b4/j_AMNS.2019.1.00016_fig_003.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6AP2G7AKOUXAVR44%2F20251005%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251005T042202Z&X-Amz-Expires=3600&X-Amz-Signature=8a462cff8def86ce9d5050936835b965236ed5b60f275770f0ff9b5b2ab20a18&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
Fig. 4
![The graphs G, H, S(G)[H], Q(G)[H], M(G)[H] and T(G)[H]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/64709ef171e4585e08aa18b4/j_AMNS.2019.1.00016_fig_004.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6AP2G7AKOUXAVR44%2F20251005%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251005T042202Z&X-Amz-Expires=3600&X-Amz-Signature=bc21c5220e256de9e243530cdac61bc96a67d90ea41dd3a6f45b3c7ddc3e49ef&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)