Landwehr, C. E., "Hidden Safety Requirements in Large-scale Systems,"  in 
  Proc. 13th World Computer Congress, IFIP Congress 94, Vol. 3, K. Duncan 
  and K. Krueger, eds., Elsevier Science B.V. (North-Holland) pp.295-302.
<a href="1994landwehr-ifip.ps">
 PostScript</a>
<p>

<blockquote>
To avoid hidden safety problems in future large scale systems, we must
be able to identify the crucial assumptions underlying the development
of their components and to enunciate straightforward rules for safe
component interconnection.
</blockquote>