Editing SSC/Structure/BonnorEbert (section)

===Ebert's Corresponding Presentation===
The expression derived by Bonnor for the ratio <math>~M_R/R</math> in the limiting configuration can be inverted to give,
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<math>
~R \approx 0.41 \biggl(  \frac{G M_R}{c_s^2} \biggr)  \, .
</math>
</div>
This matches the expression for the critical radius, <math>~R_\mathrm{kr}</math>, that appears as equation (23) in [http://adsabs.harvard.edu/abs/1955ZA.....37..217E Ebert's (1955) published derivation].  Similarly, the above relation that expresses the Bonnor-Ebert limiting mass in terms of <math>~c_s</math>, <math>~G</math>, and <math>~P_e</math> can be inverted to give,
<div align="center">
<math>
~P_e \approx 4\pi (1.18)^2 \biggl( \frac{c_s^8}{4\pi G^3 M_R^2} \biggr) = 17.5 \biggl( \frac{c_s^8}{4\pi G^3 M_R^2} \biggr) \, ,
</math>
</div>
which agrees with the limiting pressure that was derived by [http://adsabs.harvard.edu/abs/1955ZA.....37..217E Ebert (1955)] and that is also presented in his equation (23).