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index 08cd2580e2ac14b065b6fb0933bfaecf3b5982ee..9ba363f8e4b16eb1f6b1b87dcc1589c9aa6143d2 100644
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@@ -33,7 +33,7 @@ and a mattermost channel for chat. To join the mattermost channel:
 |2020-12-07|Deyan Ginev|Language and mathematics pretraining in 2021: preparing the large open datasets ([slides](https://prodg.org/talks/language_and_math_model_pretraining))|
 |2020-12-21| Deborah Mendes Ferreira | Premise Selection in Natural Language: Finding supporting facts for mathematical statements ([slides](https://docs.google.com/presentation/d/14ZVrp2kiOmthWeLBugraFdIVkd4z-PqfJMT-nlRX-e4/edit?usp=sharing)) |
 |2021-01-04| - | cancelled (too close to New Year) |
-|2021-01-18| Jan Frederik Schaefer | "Something about GLIF and MathLing" |
+|2021-01-18| Jan Frederik Schaefer | A Symbolic Framework for Mathematical Language Understanding ([slides](https://github.com/jfschaefer/slides/blob/master/2021/sigmathling/slides.pdf)) |
 |2021-02-01| Takuto Asakura | Towards Grounding of Formulae |
 |2021-02-15| ? | ? |
 |2021-03-01| ? | ? |