diff --git a/content/zettels/signal_to_noise_ratio.md b/content/zettels/signal_to_noise_ratio.md
index 1169529..92c6eb5 100644
--- a/content/zettels/signal_to_noise_ratio.md
+++ b/content/zettels/signal_to_noise_ratio.md
@@ -4,7 +4,7 @@ author = ["Thomas Dehaeze"]
 draft = false
 +++
 
-### Backlinks {#backlinks}
+Backlinks:
 
 -   [Power Spectral Density]({{< relref "power_spectral_density" >}})
 -   [Voltage Amplifier]({{< relref "voltage_amplifier" >}})
@@ -17,7 +17,7 @@ Tags
 
 ## SNR to Noise PSD {#snr-to-noise-psd}
 
-From ([Jabben 2007](#org620f0ec)) (Section 3.3.2):
+From ([Jabben 2007](#org87840a5)) (Section 3.3.2):
 
 > Electronic equipment does most often not come with detailed electric schemes, in which case the PSD should be determined from measurements.
 > In the design phase however, one has to rely on information provided by specification sheets from the manufacturer.
@@ -29,7 +29,7 @@ From ([Jabben 2007](#org620f0ec)) (Section 3.3.2):
 > \\[ S\_{snr} = \frac{x\_{fr}^2}{8 f\_c C\_{snr}^2} \\]
 > with \\(x\_{fr}\\) the full range of \\(x\\), and \\(C\_{snr}\\) the SNR.
 
-<div class="examp">
+<div class="bgreen">
   <div></div>
 
 Let's take an example.
@@ -56,7 +56,7 @@ where \\(S\_{snr}\\) is the SNR in dB and \\(S\_\text{rms}\\) is the RMS value o
 If the full range is \\(\Delta V\\), then:
 \\[ S\_\text{rms} = \frac{\Delta V/2}{\sqrt{2}} \\]
 
-<div class="examp">
+<div class="bgreen">
   <div></div>
 
 As an example, let's take a voltage amplifier with a full range of \\(\Delta V = 20V\\) and a SNR of 85dB.
@@ -73,7 +73,7 @@ The RMS value of the noise is then:
 If the wanted full range and RMS value of the noise are defined, the required SNR can be computed from:
 \\[ S\_{snr} = 20 \log \frac{\text{Signal, rms}}{\text{Noise, rms}} \\]
 
-<div class="examp">
+<div class="bgreen">
   <div></div>
 
 Let's say the wanted noise is \\(1 mV, \text{rms}\\) for a full range of \\(20 V\\), the corresponding SNR is:
@@ -84,13 +84,13 @@ Let's say the wanted noise is \\(1 mV, \text{rms}\\) for a full range of \\(20 V
 
 ## Noise Density to RMS noise {#noise-density-to-rms-noise}
 
-From ([Fleming 2010](#org094853a)):
+From ([Fleming 2010](#orgc255675)):
 \\[ \text{RMS noise} = \sqrt{2 \times \text{bandwidth}} \times \text{noise density} \\]
 
 If the noise is normally distributed, the RMS value is also the standard deviation \\(\sigma\\).
-The peak to peak amplitude is then approximatively \\(6 \sigma\\).
+The peak to peak amplitude is then approximately \\(6 \sigma\\).
 
-<div class="examp">
+<div class="bgreen">
   <div></div>
 
 -   noise density = \\(20 pm/\sqrt{Hz}\\)
@@ -104,6 +104,6 @@ The peak-to-peak noise will be approximately \\(6 \sigma = 1.7 nm\\)
 
 ## Bibliography {#bibliography}
 
-<a id="org094853a"></a>Fleming, A.J. 2010. “Nanopositioning System with Force Feedback for High-Performance Tracking and Vibration Control.” _IEEE/ASME Transactions on Mechatronics_ 15 (3):433–47. <https://doi.org/10.1109/tmech.2009.2028422>.
+<a id="orgc255675"></a>Fleming, A.J. 2010. “Nanopositioning System with Force Feedback for High-Performance Tracking and Vibration Control.” _IEEE/ASME Transactions on Mechatronics_ 15 (3):433–47. <https://doi.org/10.1109/tmech.2009.2028422>.
 
-<a id="org620f0ec"></a>Jabben, Leon. 2007. “Mechatronic Design of a Magnetically Suspended Rotating Platform.” Delft University.
+<a id="org87840a5"></a>Jabben, Leon. 2007. “Mechatronic Design of a Magnetically Suspended Rotating Platform.” Delft University.