Feel free to check out the scenario "Navigate between Sibling Energy Instances that Mitigate Earth Global Warming 2000 AD":
1. The user opens http://www.tumia.org
and selects the Tumia Class Climate Change.
2. The system displays http://www.tumia.org/en/directory/en/earth_global_warming_2000_ad_p1.html
3. The user selects a Related Instance for example Solar Energy.
4. The system displays http://www.tumia.org/en/directory/en/solar_energy_p1.html
5. The user selects some external links about Solar Energy.
6. The user selects a Related Instance (for example Hydroelecticity) that as a Sibling of Solar Energy mitigates Earth Global Warming 2000 AD.
7. The system displays http://www.tumia.org/en/directory/en/hydroelectricity_p1.html
8. The user selects some external links about Hydroelecticity.
The user repeats steps 6-8 for other sibling energy instances until done.
On the object-oriented directory Tumia "Navigate between Sibling Energy Instances that Mitigate Earth Global Warming 2000 AD" is a specific scenario of the use case "Navigate to Related Tumia Instances".
In fact this sibling relationship between the concerned energy instances is automatically derived from the link "Mitigates Earth Global Warming 2000 AD" those energy instances have in common.
Throughout Tumia these kind of sibling relationships derived from a common link are being automatically realised and presented to the user for navigating. Sibling Java Methods of the same Java Class are a similar example:http://www.tumia.org/en/directory/en/java.lang.object.getclass%28%29_p1.html