biblio command not implemented

[nus-se-bot]

Hi developers,
I've been trying to use your excellent product but I'm running into an issue when trying to use the biblio command. I've checked that it matches the command format specified and that it is not a v2.0 feature, but it doesn't work. Please advise!

Describe the bug
biblio command always errors, despite accepting a valid positive integer index as input.

To Reproduce
Steps to reproduce the behavior:

1. Run the application
2. Execute the command biblio 1

Expected behaviour
Expected to see a bibliography entry.

Screenshots

Additional context
The user guide states:

The command message states to try biblioAPA 1. However, trying this also doesn't work:

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Reported by: @thomastanck
Severity: Low

_{[original: nus-cs2103-AY1819S2/pe-dry-run#88]}