I'm looking for the origins of the isotopy extension theorem in categories other than the smooth category.   

Precisely, in the smooth category, the isotopy extension theorem says that if $f : [0,1] \times M \to N$ is a smooth 1-parameter family of embeddings (with $N$ boundaryless, and $M$ compact) then there exists $F : [0,1] \times N \to N$ a smooth $1$-parameter family of diffeomorphisms so that $F(0, \cdot) = Id_N$ and $F(t,f(0,x)) = f(t,x)$ for all $(t,x) \in [0,1] \times M$.  This was seen to be a "very natural" theorem by Palais, with the generalization stating that the restriction map $Diff(N) \to Emb(M,N)$ was not only a Serre fibration but a locally trivial fibre bundle.  In this ideal case, the references are:

* Palais, Richard S. Local triviality of the restriction map for embeddings. Comment. Math. Helv. 34 1960 305–312.

* E. L. Lima, On the local triviality of the restriction map for embeddings, Commentarii Mathematici Helvetici Volume 38, Number 1, pp 163-164.

Let $Aut(N)$ be the automorphisms of the manifold $N$ in whichever category of manifolds it lives in (topological, $PL$ or smooth).   My understanding is its known that the restriction map

$$Aut(N) \to Emb(M,N)$$

is known to be a Serre fibration provided $N$ is a co-dimension $0$ submanifold of $N$, in any of the above three manifold categories.   

My questions:

Q1: Where were these results first proven in the PL and TOP cases?  Are they known for all dimensions? 

Q2: If one allows $M$ to have co-dimension $> 0$, what is known about this map being or not being a fibration? 

I'm in the process of trying to both learn the basics and get an overview of smoothing theory.  Any help is appreciated.