Fast Entity Linker Core(FEL) https://github.com/yahoo/FEL
This library performs query segmentation and entity linking to a target reference Knowledge Base (i.e., Wikipedia). In its current version it is tailored +towards query entity linking (alternatively, short fragments of text). The main goal was to have an extremely fast linker (< 1 or 2 ms/query on average on a standard laptop) that is completely unsupervised, so that more sophisticated approaches can work on top of it with a decent time budget available. A side effect of this is that the datapack used by the linker occupies <3GB making it suitable to run on the grid (and making the footprint on server machines very low).

下面的几种来自于 CSDN昕玫的博客“【调研】关于Entity Linking（实体链接）的材料收集”

1. https://www.microsoft.com/cognitive-services/en-us/entity-linking-intelligence-service
   微软的实体链接服务（非开源），从demo看很简洁。可惜没有原理概述。

2. http://dexter.isti.cnr.it/
   dexter，一个实体链接框架。（官方的live demo都运行了半天没出结果，实用性有点令人担心）

3. https://developers.google.com/knowledge-graph/
   google的知识库检索。可以作为实体链接的一个环节来看。google的检索排名做得很好（结合知识热度/知识名/别名/正文）。

4. http://aksw.org/Projects/AGDISTIS.html
   当前流行的开源实体链接服务之一。（链接到dbpedia）

5. https://tagme.d4science.org/tagme/
   当前流行的实体链接服务之一。（链接到Wikipedia）

5. http://dbpedia.org/
   dbpedia是常见实体链接服务所使用的知识库之一。常见的知识库包括Wikipedia(https://www.wikipedia.org/.)、Freebase、YAGO、DBpedia。最常用的就是wikipedia了。