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@@ -56,6 +56,33 @@ Increasingly industry pairs vision systems for photogrammetry with laser systems
 # Tools
 <p><a href="https://www.autodesk.com/products/recap/overview?term=1-YEAR">Autodesk ReCap</a></p>
 <p><a href="https://www.agisoft.com">Agisoft Metashape</a></p>
+
+
 # Apps
+<p>iPhone and Android apps for photogrammetry and now LiDAR scanning have multiplied over the last 2 years. The primary driver is product placement, however some open source options are making way for both art and art preservation</p>
+<a href="https://www.myminifactory.com/scantheworld/">Scan the World</a>
+<p><a href="https://projectmosul.org/">Rekrei</a></p>
+<p><a href="https://www.adobe.com/products/aero.html">Adobe Aero</a></p><p><a href="https://www.adobe.com/products/aero.html">Adobe Aero</a></p>
+<p><a href="https://www.scandy.co/apps/scandy-pro">ScandyPro</a></p>
+<p><a href="https://www.bellus3d.com/faceapp/">Bellus</a></p>
+
+<p><img src="img/bellus.jpg" alt="Bellus"></p>
+
+
+
 
 # Camera Equations
+
+<p>Intrinsics and extrinsics parameters</p>
+<p><a href="https://en.wikipedia.org/wiki/Levenberg%E2%80%93Marquardt_algorithm">Levenberg–Marquardt algorithm</a> or damped least-squares algorithm (dls) are used to minimize the error across 3d coordinates. This procedure is typically called <a href="https://en.wikipedia.org/wiki/Bundle_adjustment">bundle adjustment</a>.</p>
+<p>Groundwork camera properties and standards for USGS photgrammetry surveys.</p>
+<a href="https://www.sciencedirect.com/science/article/abs/pii/0031866373900069">Welch 1973</a>
+
+# ML for Photogrammetry
+<a href="https://www.pix4d.com/blog/machine-learning-meets-photogrammetry">Pix4D</a>
+<p>Improving accuracy while scraping information on the contents of photogrammetry data sets.</p>
+
+# Open Source Photogrammetry
+
+
+# Light Field