# Mathematics Preprints List - 1991

91.01 J.B. Hughes,

*On second order sufficient conditions for optimising
with equality conditions, *

91.02
G.A. Gardner, L.R.T. Gardner, J. Cunningham and H. Yassi,

*Simulation of a fox-rabies epidemic over Kent, *

91.03 L.R.T. Gardner, G.A. Gardner and I. Dag,

*Method of lines solutions for the KdV equation
using B-spline finite elements, *

91.04 (previously 89.19b)
J. Cunningham, G.A. Gardner and L.R.T. Gardner,
*Numerical simulations of fox-rabies spread using a stochastic model, *

91.05 (previously 89.19a?)
J. Cunningham, G.A. Gardner and L.R.T. Gardner,

*Stochastic modelling of fox-rabies spread, *

91.06 J.B. Hughes,

*Quasieigenvalues and quasieigenvectors of an operator related
to a subspace of its domain,*

91.07
T. Porter,

**n**-types of simplicial groups and crossed **n**-cubes,

91.08
R. Brown,

*Computing homotopy types using crossed n-cubes of groups,*

91.09 C. Casacuberta, G. Peschke and M. Pfenniger,

*On orthogonal pairs in categories and localization, *

91.10 (replaced by 91.33) L.R.T. Gardner G.A. Gardner,

*B-spline finite elements, *

91.11 R. Brown and P.H. Higgins,

*The classifying space of a crossed complex.*

91.12 L.R.T. Gardner and G.A.G. Gardner,

*Solitary waves of the equal width wave equation. *

91.13
J. Cunningham, G.A. Gardner and L.R.T. Gardner,

*A deterministic model for the inter-population spread of epidemic typhus,
*

91.14 R. Brown, N.D. Gilbert, H.-J. Hoehnke and J. Shrimpton,

*Non-abelian tensor products of groups; groupoids; quadratic forms and
higher order symmetry. *

91.15
I Morris and C.D.Wensley,

*Cycle indices and subgroup lattices. *

91.16
I. Morris and C.D. Wensley,

*\lambda-operations in \beta-rings.*

91.17 M. Pfenniger,

*On completions. *

91.18 M. Pfenniger,

*On a pitfall in localization. *

91.19 M. Pfenniger,

*Remarks related to the Adams spectral sequence. *

91.20 M.V. Lawson,

*Coverings and embeddings of inverse semigroups. *

91.21 (previously 90.24) M.V. Lawson,

*An equivalence theorem for inverse semigroups.*

91.22 L.J. Hernandez and T. Porter,

*An embedding theorem for proper N-types, *

**Published in:**
*Top. Appl.* 48 (1992) 215-233.

91.23 (revised as 94.13) M.V. Lawson,

*The geometric theory of inverse semigroups
III: idempotent pure coextensions.*

91.24 (previously 90.26) M.V. Lawson,

*Congruences on ordered groupoids (revised version of 90.26) *

91.25 M.V. Lawson,

*Categories of monics and ordered groupoids. *

91.26 M.V. Lawson,

*Ordered groupoids and inverse categories. *

91.27 M.V. Lawson,

*Rees matrix semigroups over cancellative categories. *

91.28 L.R.T. Gardner, T. Geyikli,

*New B-spline finite element algorithms for the KdV equation.*

91.29 L.R.T. Gardner, G.A. Gardner and S.I. Zaki,

*Collisional effects in plasmas modelled by a simplified
Fokker-Planck equation. *

91.30
J. Cunningham, L.R.T. Gardner, G.A. Gardner and H. Yassi,

*Rabies spread in high density fox populations. *

91.31 A. Tonks,

*Cubical groups which are Kan. *

91.32 N.T. Nhu,

*The AR-property in linear metric spaces. *

91.33 (previously 91.10) L.R.T. Gardner, G.A. Gardner,

*B-spline finite elements.*

91.34 L.R.T. Gardner, G.A. Gardner, S.I. Zaki, Z. El-Sharawi,

*A leap-frog algorithm and stability studies for the
non-linear Schroedinger equation, *