Wirf mal einen Blick auf die Homepage der Dev7studios, dem Hersteller des Nivo Slider, da findest Du eine eindeutige Aussage zu dem Thema:

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The Nivo Slider jQuery plugin is open source and released under the MIT license. This means you can use it almost anywhere and for almost any kind of project, including personal and commercial websites and themes you make. It also means you can give back to the community by contributing your own improvements to the slider via GitHub.
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Die MIT license, die ja auch für die Zoom Widgets gilt, wird hier ausführlich erklärt.

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The MIT License (MIT)
[OSI Approved License]

The MIT License (MIT)

Copyright (c) <year> <copyright holders>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
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