Exhaustive exploration of the conformational landscape of mono- and disubstituted five-membered rings by DFT and MP2 calculations - RSC Advances (RSC Publishing) DOI:10.1039/C9RA03524A
Solved 2. A pyranose ring (6 membered ring with 5 carbon | Chegg.com
Fused Heterocyclic Rings - an overview | ScienceDirect Topics
Figure 2 from Thermodynamic analysis of strain in the five-membered oxygen and nitrogen heterocyclic compounds. | Semantic Scholar