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Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>

content/blog/01_spa_agda_lattices.md

@@ -203,6 +203,7 @@ element that's greater (less specific) than either `s1` or `s2`". Conventionally
 this function is written as \(a \sqcup b\) (or in our case, \(s_1 \sqcup s_2\)).
 The \((\sqcup)\) symbol is also called the _join_ of \(a\) and \(b\).
 We can define it for our signs so far using the following [Cayley table](https://en.wikipedia.org/wiki/Cayley_table).
+{#least-upper-bound}
 
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