### 10. References to lerfu

The rules of Section 9 make it impossible to use unmarked lerfu words to refer to lerfu themselves. In the sentence:

```10.1)  .abu. cu lerfu
A is-a-letteral.
```
the hearer would try to find what previous sumti “.abu” refers to. The solution to this problem makes use of the cmavo “me'o” of selma'o LI, which makes a lerfu string into a sumti representing that very string of lerfu. This use of “me'o” is a special case of its mathematical use, which is to introduce a mathematical expression used literally rather than for its value.
```10.2)  me'o .abu cu lerfu
The-expression “a” is-a-letteral.
```
Now we can translate Example 1.1 into Lojban:
```10.3)  dei vasru vo lerfu
po'u me'o .ebu
this-sentence contains four letterals
which-are the-expression “e”.
This sentence contains four “e”s.
```
Since the Lojban sentence has only four “e” lerfu rather than fourteen, the translation is not a literal one — but Example 10.4 is a Lojban truth just as Example 1.1 is an English truth. Coincidentally, the colloquial English translation of Example 10.4 is also true!

The reader might be tempted to use quotation with “lu ... li'u” instead of “me'o”, producing:

```10.4)  lu .abu li'u cu lerfu
[quote] .abu [unquote] is-a-letteral.
```
(The single-word quote “zo” cannot be used, because “.abu” is a compound cmavo.) But Example 10.4 is false, because it says:
```10.5)  The word “.abu” is a letteral
```
which is not the case; rather, the thing symbolized by the word “.abu” is a letteral. In Lojban, that would be:
```10.6)  la'e lu .abu li'u cu lerfu
The-referent-of [quote] .abu [unquote] is-a-letteral.
```
which is correct.