If the question is how to "get" instead of where to "buy" quality backlinks then, this is my answer.
Don´t only focus on quality, you also need to heavily focus on relevance.
As stated by Google itself, relevance is a major ranking factor.
It won´t do much for your site´s SEO getting a link from IBM when your site is about pets.
Acquiring quality backlinks is really hard but, doing it within your niche, it´s a skill.
In order to acquire high-quality and
RELEVANT links, you need to focus on these factors...
- Have a fully optimized site for both technical and on-page factors
- Publish high-quality, in-depth and SEO optimized articles that matches Google user´s search intent
If you cover these areas, high-quality and relevant links will come naturally to you and, it will make your job of "finding" or "building" links a hell lot easier.