> For the complete documentation index, see [llms.txt](https://developer.nilvera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.nilvera.com/en/api/e-archive-invoice-api/e-fatura-goenderme.md).

# Sending an Invoice

{% hint style="success" %}
Not: Sending the API key as Authorization:Bearer {API\_KEY} in the Header field of your service calls will be enough for the API to recognize and authorize you.
{% endhint %}

## Authentication

<table data-header-hidden><thead><tr><th width="377.3333333333333"></th><th></th><th data-hidden></th></tr></thead><tbody><tr><td>AuthenticationSecurity Scheme Type</td><td>Http</td><td></td></tr><tr><td>HTTP Authorization Scheme</td><td>Bearer</td><td></td></tr><tr><td>Bearer Format</td><td>APIKEY</td><td></td></tr></tbody></table>